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March 2010 Preventing the spread of infectious diseases in the European Union – targeted hygiene as a framework for sustainable hygiene March 2010 Authors: Professor Sally F. Bloomfield1, Professor Martin Exner2, Professor Kumar Jyoti Nath3, Mr John Pickup4, Professor Elizabeth A Scott5, Professor Carlo Signorelli6 1London School of Hygiene and Tropical Medicine, London, UK. Institute for Hygiene and Public Health, Rheinische Friedrich-Wilhelms-Universität, Bonn, Germany. 3Chairman, Sulabh International Social Service Organization, Calcutta, India. 4Consultant in Scientific Issues, Bridgnorth, Shropshire, UK. 5Director Of Undergraduate Program in Public Health, Co-director Simmons Center for Hygiene and Health in Home and Community, Simmons College, Boston, MA USA. 6Department of Public Health, University of Parma, Italy. 2Director, A report by the International Scientific Forum on Home Hygiene 2 This report was commissioned by Unilever who requested IFH to review the IFH targeted approach to home hygiene as a framework for developing a sustainable approach to hygiene. Most particularly IFH was asked to address the need to balance concerns about environmental and human safety against recognition of the important role of hygiene, and the need to ensure that EU citizens have access to effective codes of hygiene practice, and hygiene products and processes, to protect themselves against infectious disease. The full report can be downloaded from the IFH website at: http://www.ifhhomehygiene.org/IntegratedCRD.nsf/f5236e2da2822fef8025750b000dc985/62812e8 ac19247fe802576c60054693f?OpenDocument The International Scientific Forum on Home Hygiene (IFH; www.ifhhomehygiene.org) is a not for profit, non governmental organisation which was established in 1997 to meet the need for an independent expert body who could develop and promote a science-based approach to hygiene in home and everyday life settings as a means to reduce the global burden of infectious diseases. 3 Contents CONSENSUS STATEMENT 5 REPORT SUMMARY 8 1. INTRODUCTION 17 2. THE BURDEN OF HYGIENE-RELATED INFECTIOUS DISEASES IN THE EUROPEAN UNION 18 2.1 INFECTIOUS INTESTINAL DISEASES 19 2.2 RESPIRATORY INFECTIONS 21 2.3 SKIN INFECTIONS - STAPHYLOCOCCUS AUREUS AND MRSA 21 2.4 FUNGAL INFECTIONS 22 2.5 ANTIBIOTIC RESISTANCE 23 2.6 PETS AND DOMESTIC ANIMALS AS A SOURCE OF INFECTION IN THE HOME 24 2.7 AT-RISK GROUPS IN THE HOME AND COMMUNITY 24 2.8 THE IMPACT OF SOCIAL DETERMINANTS ON THE SPREAD OF INFECTIOUS DISEASES 25 2.9 THE IMPACT OF SOCIAL TRENDS ON THE SPREAD OF INFECTIOUS DISEASES 26 2.10 CHRONIC SEQUELAE OF INFECTIOUS DISEASES 27 3. DEVELOPING A RISK-BASED APPROACH TO HOME HYGIENE 27 3.1 IDENTIFYING CRITICAL CONTROL POINTS IN THE CHAIN OF INFECTION TRANSMISSION IN THE HOME 28 3.2 APPLYING HYGIENE PROCEDURES TO BREAK THE CHAIN OF INFECTION IN THE HOME 30 3.2.1 Hygiene procedures to prevent cross contamination during food preparation 30 3.2.2 Hygiene procedures to prevent spread of norovirus between family members 33 3.2.3 Hygiene procedures to prevent transmission of MRSA via clothing and household linens 33 4. ESTABLISHING THE LINK BETWEEN TARGETED HYGIENE AND HEALTH BENEFITS 36 5. IFH – DEVELOPING AND PROMOTING THE TARGETED APPROACH TO HOME HYGIENE 37 6. SUSTAINABLE HYGIENE – THE KEY FACTORS 38 7. TARGETED HYGIENE – A FRAMEWORK FOR SUSTAINABLE HYGIENE IN THE HOME AND EVERYDAY LIFE 42 8. CONCLUSIONS AND RECOMMENDATIONS 43 REFERENCES 46 4 CONSENSUS STATEMENT Across Europe, infectious diseases continue to be a significant health and economic burden: New pathogens (including antimicrobial resistant strains) such as MRSA, avian and swine influenza and SARS are continually emerging. At the same time, social and demographic changes mean that people with reduced immunity to infection, who are more vulnerable to infection, make up an increasing proportion of the population (currently up to 20%). Infectious diseases can act as co-factors in other diseases that manifest at a later date, such as cancer and chronic degenerative diseases, or as triggers for development of allergic diseases such as asthma. These ongoing changes demand new containment strategies, increasingly involving the community as a whole. A number of interrelated factors need consideration. For example: Whereas there has been a tendency to assume that common respiratory and foodborne infections circulating in the community are a minor concern, in reality the total burden in terms of absence from work and school is considerable. Community and hospital care for vulnerable groups who become seriously ill, or for those who develop ongoing sequelae are an additional healthcare cost. Technological and policy changes are being introduced to reduce costs and/or environmental effects without regard to their potential impact on infectious disease risks. Governments are under considerable pressure to fund the level of healthcare that people expect, and are now looking at disease prevention strategies as a means to reduce health spending. Hygiene is increasingly recognised as a cost effective means to reduce the burden of infectious diseases within the European Union (EU). Increased homecare is one approach to reducing health spending, but, for this to be effective, it must take account of the fact that gains are likely to be undermined by inadequate infection control at home. Targeted Hygiene & Sustainability A parallel agenda of global importance is sustainable development, a concept that refers to meeting the needs of society, and improving quality of life, in a way that does not jeopardise the ability of future generations to meet theirs. Protecting health by preventing infection is an intrinsically more sustainable approach than treatment. Hygiene has the potential directly to improve sustainability because its aim is to promote and protect health. However, hygiene measures must themselves be sustainable, which means that issues such as the environment, concerns about antibiotic resistance, and the much publicised notion that “we have become too clean for our own good” need to be assessed and managed. In response to the need for more emphasis on hygiene promotion in our homes and everyday lives, the International Scientific Forum on Home Hygiene (IFH) has developed a new approach to hygiene in the home and community, which is designed to meet 21st century needs and support new community hygiene promotion programmes. This approach is based on scientific data and risk assessment, and is known as “targeted hygiene”. The aim of this approach is to maximise protection against exposure to infectious microbes (germs) by breaking the chain of infection 5 transmission at critical points, before germs can spread any further. In some situations, this is readily achieved by physical removal alone using cleaning products such as hand soap, and rinsing with clean water. But in some situations, processes that also inactivate germs, using heat or biocidal hygiene products and processes, are needed to ensure effective and reliable results, and protection from infection. The simple principle is that protecting the public from infection is not about unfocussed daily or weekly deep down cleaning, but about acting where and when there is risk of spread of infection. Whilst targeted hygiene was originally developed by IFH as an effective approach to hygiene practice in the home and community, it also provides an excellent framework for building sustainability into hygiene. Through prudent and focussed use of hygiene products and processes, it intrinsically minimises their life-cycle impacts, maximises safety margins against any hazards and minimises any risks of encouraging the development of antibiotic resistance through low level biocide exposure. It also seeks, as far as possible, to sustain “normal” levels of exposure to the microbial flora of our environment to the extent that is important to build a balanced immune system. Developing and Promoting Hygiene within the European Union Governmental bodies both at regional and national level are now working to develop strategies that respond to the need for greater emphasis on hygiene. A key element is the establishment of the European Centre for Disease Control and Prevention (ECDC). The EU-funded “e-Bug” project http://www.e-bug.eu/ is also working to roll out education on antibiotic resistance and hygiene at primary and secondary school level across Europe. Recent years have seen significant investment in food hygiene, handwashing and, most recently, respiratory hygiene campaigns aimed at reengaging the public and changing behaviour. IFH is working to support hygiene promotion activities by producing home hygiene guidelines, training resources and fact/advice sheets based on the targeted hygiene approach. The Role of Biocidal Products Sustainable use of biocidal hygiene products (i.e Biocidal products which act against bacteria, viruses, fungi etc), in terms of life-cycle impacts and human and environmental safety, can be assessed just as for other cleaning products and ingredients. The Biocidal Products Directive (BPD) requires human health and environmental risk assessments to be prepared in the coming years for all biocides in relation to their uses. Individual biocidal products will also require authorisation under BPD. Those not giving satisfactory risk assessments will be restricted or removed from the market. IFH is concerned that the environmental and safety assurance of hygiene processes and products must not be addressed in isolation: the potential risks must be balanced against EU citizens’ need for effective means of protecting themselves against the real and continuing harm caused by infectious disease, which may require the use of biocidal products or other biocidal processes involving e.g. heat, UV irradiation, etc. There is also in the EU an increasing focus on how to control antibiotic resistance, and protect health with less reliance on antibiotics. As antibiotic resistance continues to reduce our ability to treat infections, infection prevention through effective hygiene becomes of even greater importance. By reducing the number of infections through good hygiene, which in some cases requires the use of a biocidal 6 hygiene product, the number of courses of antibiotic treatment can be reduced, which can in turn reduce the impact of antibiotic resistance. Conclusions and Recommendations One thing that is increasingly obvious is that if the burden of infectious diseases is to be reduced in an economically sustainable manner, the responsibility must be shared by the public. The key question is how do we achieve this? One problem that hinders progress is that the responsibility for public health within Europe is structured such that the separate aspects of home hygiene – food hygiene, hand washing, pandemic flu preparedness, etc – are dealt with by separate agencies. If hygiene promotion is to be successful in changing behaviour, we need an integrated family-centred (rather than agency-convenient) approach to ensure a basic understanding of infectious disease agents and how they spread , together with an understanding of which people can adapt to meet changing needs. Hygiene needs to be repositioned alongside other values of healthy living such as good diet and exercise rather than something that is old fashioned, unnatural and potentially unhealthy. IFH concludes that if we are to sustain a high level of protection for EU citizens against infectious disease, in the face of changing demographics and microbial evolution, and at the same time derive real health benefits from investment in hygiene promotion, the various stakeholders (public health bodies and health professionals, environmentalists, immunologists, regulatory bodies and the private sector) need to work together to develop an integrated approach to public hygiene and hygiene promotion that takes account of and balances all of these issues. We must build a more family-centred approach to hygiene that recognises the importance of infectious disease prevention as a public health measure and ensures the people of the EU have effective, safe and sustainable means of achieving this. Professor SF Bloomfield Mr J Pickup London School of Hygiene and Tropical Medicine, London, UK Consultant in Scientific Issues, Bridgnorth, Shropshire, UK Professor M Exner Professor EA Scott Institute for Hygiene and Public Health, Rheinische Friedrich-Wilhelms-Universität, Bonn, Germany Simmons College, Boston, MA, USA Professor KJ Nath Professor C Signorelli Dept of Public Health, University of Parma, Parma, Italy Sulabh International Social Service Organization, Calcutta, India International Scientific Forum on Home Hygiene. February 2010. 7 REPORT SUMMARY In the late 1960s, the Surgeon General of the United States of America is alleged to have said “it is time to close the book on infectious diseases, declare the war against pestilence won, and shift national resources to such chronic problems as cancer and heart disease". The last 40 years have shown that this optimism was misplaced; infectious diseases are a continuing and significant burden on the health and prosperity of the global community, not only in the developing world, but also in developed world areas such as the European Union (EU). Across the world, governments now recognise the need for more investment in infectious disease surveillance and prevention strategies involving measures such as immunisation and hygiene. Increasingly, this includes strategies to reduce the spread of infection within the family at home, and in their everyday lives; there is a realisation that, if the global burden of hygiene-related disease is to be reduced in a manner that is economically sustainable it has to be a responsibility that is shared by the public. A key response in Europe has been the establishment of the European Centre for Disease Control and Prevention (ECDC). A parallel agenda of global importance is sustainable development. Health is at the heart of social sustainability, whilst poor health is a major drain on economic sustainability. Hygiene seeks to promote and protect health by preventing infection and is intrinsically a more sustainable approach than treatment. Of equal importance is that hygiene measures must themselves be sustainable; hygiene needs to be delivered in a way that is effective and efficient in social, economic and environmental terms. In developing and promoting public hygiene strategies, various potential impacts need to be assessed and managed appropriately: Life-cycle environmental impacts of hygiene procedures and products, including the assurance of safety. Concerns that use of certain biocidal products could encourage the development and spread of antibiotic resistance, and that widespread use of certain biocides may lead to resistance to those biocides. The notion that lack of “exposure to infection” may be contributing to the increased incidence of allergic diseases such as asthma and hay fever etc. Currently, within the EU, various processes are being implemented that bear on the above, notably initiatives on Sustainable Consumption and Production, the REACH Regulation (Registration, Evaluation and Authorisation of Chemicals) and the Biocidal Products Directive (BPD). There is also a focus on how to control antibiotic resistance, and protect health with less reliance on antibiotics. We are also beginning to gain a better understanding of the link between microbial exposure and development of allergic diseases. Unfortunately, these issues – infectious diseases, sustainability, environmental issues, product safety, antibiotic resistance and allergic diseases – tend to be addressed in isolation, often by separate agencies, such that there is relatively little opportunity to address and balance the incompatibilities between them. IFH is concerned that, particularly in Northern Europe, environmental and safety concerns, including about hygiene and hygiene products, have been the major focus, with little attention paid to the need for effective means of reducing the burden of infectious diseases. If we are to deliver maximum health benefit in a manner that is sustainable, and engage the public in sharing responsibility for reducing infectious diseases, it is of paramount importance that the benefits and risks are properly weighed. 8 IFH has prepared this report in order to highlight the importance and potential of “everyday life” hygiene to contribute to a more sustainable future by reducing the social and economic burden of infectious disease, and to propose a strategy for achieving this, which is itself sustainable. IFH has used the available scientific data to formulate a risk-based or ‘targeted’ approach to hygiene in the home and community. Whilst targeted hygiene, as outlined in this report, was adopted by IFH as a means to develop an effective code of hygiene practice for the home, it also provides an excellent framework for ensuring the hygiene measures used are themselves sustainable. The burden of hygiene-related infectious disease in the European Union In the last 20 years or more, a number of events and/or trends can be identified that have necessitated investment in public hygiene promotion campaigns. Many of these derive from the constantly changing nature and range of pathogenic microbes to which we are exposed. Despite significant investment, food-related, waterborne, and non-food-related infectious intestinal diseases remain at unacceptably high levels. In 2003, the World Health Organisation assessed that about 40% of reported foodborne outbreaks in the European Region occur in private homes; in theory food poisoning is 100% preventable through good food hygiene. Hygiene also plays a part in limiting the spread of respiratory infections such as colds and influenza. The threat posed by emerging diseases such as avian influenza, SARS and swine flu has prompted the realisation that, in the event of a pandemic, hygiene is an important first line of defence during the early critical period before mass vaccination becomes available. Whereas there has been a tendency to assume that common gastrointestinal, respiratory and skin infections circulating in the community are a minor concern, the burden in terms of absence from work and school, together with increased pressure on health services, is considerable. Data also increasingly show that seemingly minor infectious diseases can act as co-factors in other diseases that manifest at a later date, such as cancer and chronic degenerative diseases, or as triggers for the development of allergic diseases. A major focus within the EU is containing the threat from antibiotic resistance, which increasingly undermines our ability to control infectious disease. Alongside prudent antibiotic prescribing, hygiene is now seen as a key strategy for reducing the impact of antibiotic resistance, by reducing the need for antibiotic prescribing and reducing the circulation of antibiotic-resistant strains both in hospitals and the community. The situation with regard to infectious disease is exacerbated by the ongoing social, demographic and other changes that mean that people with reduced immunity to infection now make up an increasing proportion of the global population - maybe as much as 20%. The largest proportion are the elderly who have co-morbidities, which can result in reduced immunity to infection. It also includes the very young, patients discharged from hospital, taking immunosuppressive drugs or using invasive systems, etc. Governments are under pressure to fund the level of healthcare that people expect. Care of increasing numbers of patients in the community, including at home, is one answer, but can be fatally undermined by inadequate infection control in the home. Across Europe, there is an inequitable distribution of communicable diseases. Populations at higher risk of infection coincide with those with a low level of education, occupational class, or income level. In low income populations, malnutrition also contributes to increased susceptibility to infection. These factors can initiate a “vicious cycle” of infection predisposing to malnutrition and growth faltering, which in turn leads to increased risk for further infection. 9 Technological advances are also being introduced to save costs or reduce environmental impact without proper regard to their impact on infectious disease risks. Trends in social behaviour and eating habits are increasing the risks of transmission of infectious disease amongst family members at home. The demand for different and “exotic foods” stimulates increasing movement of foodstuffs from one region or country to another and creates problems in controlling microbial quality, whilst increased population mobility means that new pathogens can be rapidly spread into communities where there is little or no resistance. The International Scientific Forum on Home Hygiene (IFH) – developing a riskbased, ‘targeted’ approach to home hygiene The International Scientific Forum on Home Hygiene (IFH) is a global, professional, non-government organisation which was established in 1997 to meet a growing need to develop and promote an effective approach to home hygiene based on sound scientific principles. To achieve this, IFH has drawn on the expanding volume of scientific data, to formulate a risk-based approach to home hygiene. Risk management is the standard approach for controlling microbial risks in food and other manufacturing environments, and is becoming accepted as the optimum means to prevent such risks in home and hospital settings. Applied to the home, this has come to be known as “targeted hygiene”. Targeted hygiene starts from the recognition that pathogens are introduced continually into the home, by people (who may have an infection or may be asymptomatic carriers), contaminated food and domestic animals, but also sometimes in water or via the air. Additionally, sites where water accumulates such as sinks, toilets, waste pipes, or items such as cleaning cloths readily support microbial growth and can become primary reservoirs of infection; although species are mostly those that represent a risk to vulnerable groups. In many homes, there will also be at least one family member who is more susceptible to infection for one reason or another. Within the home there is a chain of events (see Figure 1) that results in transmission of infection from its source to a new recipient. The simple principle is that, if we can break the chain of infection transmission, infection cannot spread. Figure 1: The chain of infection 10 A risk-based approach to hygiene examines each stage of the infection transmission cycle in order to identify the “critical control points” for preventing spread. This allows sites and surfaces to be ranked according to the level of risk; this indicates that in the home the “critical points” are the hands, together with hand and food contact surfaces, cleaning cloths and other cleaning utensils. These form the “superhighways” for spreading pathogens around the home such that healthy family members become exposed, directly or via the food they eat. Although this is a useful “rule of thumb” ranking, it is not constant: in certain situations it can be quite different and varies markedly at different times and according to circumstances. Toilets were invented for controlling risks associated with human waste, but this does not mean they are zero risk. They still have risks associated with them, which may become critical at certain times e.g. when someone in the home has sickness or diarrhoea. Targeted hygiene also means applying a suitable hygiene procedure at appropriate times to interrupt the chain of infection. It is known that, even for healthy family members, the infectious dose for some pathogens can be very small (10-100 viable units or even less for some viruses) and that infection can result from direct transfer from surfaces via hands or food to the mouth, nasal mucosa and conjunctiva. On this basis IFH consider that, in risk situations, a 'hygienic cleaning' procedure should be used to eliminate as many organisms as possible from critical surfaces. Hygienic cleaning can be done in one of two ways: By mechanical removal involving soap or by detergent-based cleaning with rinsing. The soap or detergent maximises detachment of microbes from surfaces. To be effective this process must be accompanied with thorough rinsing under running water that is disposed of safely from the home (e.g. into the public wastewater system) such that pathogens cannot be further disseminated around the home. By using a process or product that inactivates the pathogens in situ. Germ kill is usually achieved using a disinfectant product or waterless hand rub, or by the application of heat. Alternatively a combination of germ removal with kill can be used, e.g. clothing and household linens should be laundered at 60ºC, but hygienic cleaning can also be achieved using laundry wash and rinse cycles at 40ºC, using a bleachcontaining laundry product. Domestic dishwashers employ a combination of heat and detergent-based cleaning with rinsing to decontaminate cooking and eating utensils. Even today, there is still a body of expert opinion that holds to the view that, in home and everyday life hygiene, soap and water are all that is required, there is no need for biocidal products. This recommendation makes the assumption that this process is consistently effective as a “hygienic cleaning” process. The data presented in the full IFH reportError! Bookmark not defined.1 clearly show that, in some situations, soap and water alone are insufficient to eliminate contamination from critical control points and, in reality, can be a very effective means of spreading contamination from one surface to another. In these situations it is necessary to use a process, such as the application of a biocidal product, waterless hand rub, or the use of heat, UV irradiation or other process that inactivates microbes in situ. An argument put forward against use of biocidal products or processes is that, although the germ removal by cleaning alone is less than that which can be achieved by the use of biocidal products and processes, it is sufficient to produce hands, surfaces and fabrics that can be considered as safe i.e. for which the level of residual germs is no longer a threat to health. This is despite the fact that data increasingly show that the infectious dose for many common pathogens, particularly viruses, can be very small. It also takes no account of the fact that a substantial proportion of “healthcare”, the care of 11 at-risk groups who are more susceptible, and to lower doses of pathogens, now takes place in the home. The benefits of maximising germ removal from critical surfaces have been demonstrated by application of quantitative risk modelling to hand hygiene. This shows that although the benefit of using alcohol hand rubs, which increase the log reduction on hands (as compared with handwashing with soap), is not measurable in terms of the individual, it can translate into a significant decrease in disease burden within a community. Hygiene and sustainability – the key issues Sustainability and sustainable development are concepts that refer to meeting the needs of society, and improving quality of life, in a way that does not jeopardise the ability of future generations to meet theirs. Hygiene has the potential directly to improve sustainability because its aim is to promote and protect health. The hygiene measures used, however, must themselves be not only safe, but sustainable. Most aspects of the sustainability of hygiene measures, notably those involving environmental impacts or safety, are typical of those arising in product and process life cycles generally. A key tool is Life Cycle Assessment (LCA) which evaluates the significant environmental impacts of products or processes in terms of inputs required (such as materials, energy, water) and outputs (such as emissions and waste). It is eminently applicable to evaluating the sustainability of hygiene products (such as soaps, cleaners, disinfectants, paper towels) and procedures (such as washing in hot water or heat sterilisation). However, while LCA can ascribe numerical values with some accuracy to individual impacts from a particular process, the relative importance of different types of impact is subjective and variable according to prevailing conditions and even value judgements. In most cases, assessments are concerned with comparing options, rather than ascribing exact values. Decisions need to be based on comparison of alternative ways of delivering the same result. Desired results must be defined, not only in terms of e.g. acceptable contamination levels but also the reliability or likelihood with which they can be achieved. A sine qua non is assurance of safety for people and the environment. This can be assessed using well-established chemical risk assessment techniques, and manufacturers have clear responsibilities to ensure the safety of their products. Such assessments are now a formal requirement under the REACH legislation and/or the BPD. Two specific possible long-term impacts, however, need additional consideration: Sustainability of hygiene as an infection prevention measure In delivering disease prevention through hygiene, on one hand, hygiene should optimise protection against exposure to harmful microorganisms, but on the other, it should minimise disruption of natural flora of the human body and the environment. A particular concern, presently, is the so-called hygiene hypothesis. From a review of the evidence IFH has concluded that, although there is good evidence that microbial exposure in early childhood can protect against allergies, there is no evidence that we need exposure to harmful microbes or to suffer a clinical infection. Nor is there evidence that hygiene measures such as handwashing, food hygiene etc. are linked to increased susceptibility to atopic disease. If this is the case, there is no conflict between the goals of preventing infection and minimising allergies. A consensus is now developing among experts that the answer lies in more fundamental changes in lifestyle that have led to decreased exposure to certain microbial or other species, such as helminths, that are important for development of immuno-regulatory mechanisms. There is still much uncertainty as to which lifestyle factors are involved. 12 Although alarmist media coverage of the hygiene hypothesis has declined, a strong ‘collective mindset’ has become established that dirt is ‘healthy’ and hygiene somehow ‘unnatural’. This has caused concern among health professionals that everyday life hygiene behaviours, which are the foundation of public health, are being undermined. Without clear evidence of the need for exposure to infectious doses of pathogens to develop a healthy immune system, set against the firm knowledge that germ exposure can cause disease, encouraging lower standards of hygiene in the hope it might reduce the burden of allergic diseases would be a reckless and illadvised strategy with potential adverse consequences for public health. We are only now beginning to understand how the normal resident and environmental microbial flora interact within the body to maintain a healthy immune system. Sustainability of the use of biocidal products and other biocidal processes An implicit part of the IFH targeted hygiene approach is that, if we are to deliver hygiene at the critical points, as needed to break the chain of infection, biocidal products and processes are required in certain situations. Biocides, however, are not a fundamentally distinct group of compounds; many substances have significant biocidal action against microbes, but this does not per se mean they have very different, or more adverse, safety and environmental profiles. Sustainable use of biocides and biocidal products in terms of life-cycle impacts, and human and environmental safety can thus be assessed and assured just as for other cleaning products. The BPD requires human health and environmental risk assessments to be prepared in the coming years for all biocides in relation to their uses. Individual biocidal products will also require authorisation under BPD. Those not giving satisfactory risk assessments will be restricted or removed from the market. Once the safety of a biocidal product is assured as above, it could be argued that sustainability improvement could then be addressed by reducing the life-cycle impacts of the formulation and its ingredients. However, if all other things are equal, it makes sense that ingredients with more favourable environmental and human safety profiles should be preferred, as this could usefully increase margins of safety and provide added assurance for the future against any hitherto unsuspected effects. Favourable environmental safety characteristics include ready degradation or removal during sewage treatment, and low lipophilicity and thus a low potential to bioaccumulate. Ingredients with wide margins of safety, whose hazards are well understood and characterised, should be preferred to those where there is greater uncertainty. A further question is whether disinfectant usage is encouraging the emergence of antibiotic-resistant 'superbugs'. From literature reviews in 2002 and 2004, IFH concluded that, although laboratory experiments demonstrate links between biocide exposure and increased resistance to antimicrobials, there is currently no evidence that biocide use in the community is linked to emergence and spread of antibiotic resistance; antibiotic misuse is the most significant causative factor. These conclusions differ in emphasis from those expressed in a 2009 report from the EU Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) that concluded that current scientific evidence does indicate that use of certain types of active substances in biocidal products in various settings may contribute to increased occurrence of antibiotic resistance. Overall, however, both the IFH and SCENIHR reports stress the important role of biocides in the control of microbes in a variety of applications. Both reports caution that biocides are a precious resource that must be managed through appropriate and prudent use. IFH further concludes, as have others, that as antibiotic resistance continues to reduce our ability to treat infections, infection prevention through hygiene in hospitals and the community becomes of even greater importance. By reducing the number of infections through effective 13 hygiene, which in some cases may require the use of a biocidal hygiene product, the number of antibiotic courses prescribed can be lowered, which can in turn reduce the impact of antibiotic resistance. IFH has also addressed concerns that widespread biocide usage may cause resistance to those biocides. After review, IFH has concluded that, although laboratory studies provide evidence that prolonged exposure to low levels of certain biocides can be associated with reduced microbial susceptibility to those biocides, there is currently no evidence that biocide usage at its current levels in domestic and other settings compromises effectiveness of hygiene procedures under use conditions. Again, however, prudent use is the sustainable approach. Targeted hygiene – a framework for sustainable hygiene in the home and everyday life The essence of targeted hygiene is that it works to ensure that, as far as possible, hygiene interventions are focussed on situations where they maximise protection against infection, rather than in situations where there is little risk. Whilst targeted hygiene was originally adopted by IFH as a means to develop an effective code of hygiene practice for the home, it also provides a framework for sustainable hygiene because, through prudent and focussed use of hygiene products and processes, it: minimises the life-cycle impacts of hygiene processes, and maximises safety margins against any hazards of their use minimises any risks of development of antibiotic resistance from exposure to low level biocide residues seeks, as far as possible, to sustain “normal” levels of exposure to the microbial flora of our environment to the extent that it is important to build a balanced immune system. In developing and/or selecting biocidal products or processes for use within a targeted approach to hygiene, a number of issues need to be considered in order to satisfy the above criteria and thereby maximise sustainability: We need to select the most appropriate biocides. This means selecting, as far as possible: Biocides that are effective against the spectrum of organisms that represent a risk in the particular situation in which it will be used. Biocides that have a rapid biocidal action in order to break the chain of infection transmission (e.g. on hands, hand contact and food contact surfaces) with minimum delay. Note: In some situations (e.g. controlling growth of potentially harmful fungal contamination on damp surfaces such as tiled walls) a sustained biostatic (growth inhibiting) action is appropriate Biocides and biocidal products that are not environmentally persistent or bioaccumulative, for which potential adverse effects are well characterised and understood, and where there are good margins of safety. We need to think more innovatively about delivery of hygiene. For example, can we use our growing understanding of microbial attachment and detachment to better design products and processes that combine prevention of germ attachment, germ removal and control (germ kill) to deliver the necessary hygiene result in a more sustainable way? We need to ensure that, as far as possible, we use “doses” of biocidal products and processes (cleaning, biocidal and physical agents either singly alone or in combination) that achieve hygienic cleaning of sites, surfaces, fabrics etc with minimum use of water, power or chemicals. This in turn depends on developing 14 in use/field test models that more closely mimic conditions of use and allow comparison of processes that involve germ removal as well as germ kill. We need to think more holistically about delivery of hygiene in relation to sustainability i.e. in developing and selecting the most suitable hygienic cleaning method for any situation, we need to consider ALL factors (infectious disease prevention, environmental and human safety, sustainability, antimicrobial resistance, the immune system) rather than each factor in isolation. The key to targeted hygiene is that good hygiene is not a 'once weekly deep down clean': it needs to be an ongoing part of our daily lives such that appropriate measures are targeted where and when necessary. Hygiene requires well-formulated products, which deliver “hygienic cleaning” through germ removal or kill (or combinations of processes) in order to break the chain of infection transmission. Targeted hygiene will not be delivered by adding arbitrary amounts of biocides to cleaning products in order to give a “bit of extra hygiene”. Conclusions and Recommendations In the last 20 years we have seen significant investment across Europe in controlling and reducing the burden of infectious diseases, not only with the establishment of ECDC, but also through national hygiene promotion programmes. In the UK, for example, there has been an extensive programme to promote food hygiene at home. In recent months we have seen investment in promotion of hand hygiene as a means to mitigate the spread of the 2009 pandemic H1N1 influenza strain. IFH believes however that the impact of hygiene promotion programmes on the public is being weakened by the fact that the different aspects of hygiene are dealt with by separate agencies. This means that the information that the family receives is fragmented and largely rule-based. If things are to improve we must recognise that fragmented, rulebased instructions are not enough to meet the challenges we face. At the very least we must ensure that the principles of infectious disease transmission and hygiene are part of the school curriculum. In line with this, the EU-funded e-Bug project (http://www.e-bug.eu/) is working to roll out education on antibiotic resistance and hygiene at primary and secondary school level across Europe. In this review the targeted- or risk-based approach to home hygiene, as developed by the IFH, is outlined. The aim of this approach is to maximise protection against exposure to infectious agents by breaking the chain of infection transmission. This is achieved by the timely application of processes that eliminate or control microbial contamination at critical points in the chain of transmission. If we are to deliver “hygiene” (i.e. a level of contamination not harmful to health) at the critical points, targeted hygiene requires the use of not only cleaning but also, in certain situations, biocidal hygiene products and processes (either alone or in combination with germ removal). In developing and promoting hygiene practice, the issue of sustainability must also be addressed. The report1 shows that the IFH targeted hygiene approach provides a framework for building sustainability into hygiene because it minimises the life-cycle impacts of hygiene processes, maximises safety margins against any hazards of their use, and minimises any risks of the development antibiotic resistance from exposure to biocides. It also looks to sustain “normal” interaction with the microbial flora of our environment. If we are to sustain a high level of protection for EU citizens against infectious disease, in the face of changing demographics and microbial evolution, and derive 15 real health benefits from investment in hygiene promotion, IFH concludes that the various stakeholders need to work together to address the following issues: The public must be engaged so that they share the burden and bring the unique contribution that only they can make, through good hygiene in the home and community. To achieve this, hygiene promotion strategies should: Be family-centred rather than agency-oriented, building on what people understand, know and need to know. Not only change behaviour but also engender more positive attitudes to hygiene as a means to achieve health, well being and prosperity. Give people the opportunity for a more balanced understanding of how to protect themselves from infectious diseases in a world where they also have conflicting concerns about issues such as allergic diseases and the environment. The risk-based ‘targeted’ approach to home hygiene should be adopted as the basis for development of hygiene codes for the home and everyday life since it offers both the most effective approach to breaking the chain of infection transmission as well as an intrinsically more sustainable framework. Within the targeted approach to home hygiene, we need not only cleaning products that facilitate germ removal, but also biocidal products and processes are required. These provide germ inactivation, alone or in combination with cleaning processes, which can be used to ensure the elimination of pathogenic contamination from critical control points when used by consumers. The selection of products or processes for hygiene tasks should be based on assessment of their sustainability and safety as well as reliability in delivering the required result. This can be assessed using well-established tools such as lifecycle assessment and risk assessment. Additional potential impacts on bacterial resistance and immunity need to be considered and any risks weighed against the risks and impacts of infectious disease, and managed appropriately. The European regulatory process should: Encourage and facilitate the development and marketing of products and processes that deliver hygiene in a safe and sustainable way, using combinations of germ removal and germ kill as appropriate. Encourage manufacturers to develop test methods that model use conditions in order to ensure optimum efficacy and reliability with minimum impact throughout the life cycle. 16 1. INTRODUCTION In the late 1960s, the Surgeon General of the United States of America is alleged to have said “it is time to close the book on infectious diseases, declare the war against pestilence won, and shift national resources to such chronic problems as cancer and heart disease". The last 40 years have shown that this optimism was misplaced; infectious diseases are a continuing and significant burden on the health and prosperity of the global community, not only in the developing world but also in developed world communities such as the European Union (EU). Across the world, governments now recognise the need for more investment in disease prevention strategies involving measures such as immunisation and hygiene. Increasingly, this includes strategies to reduce the spread of infection within the family at home, and in their everyday lives; there is a realisation that, if the global burden of hygiene-related disease is to be reduced in a manner that is economically sustainable, it has to be a responsibility that is shared by the public. This is not about shifting blame, it is about facing reality. Recent years have seen significant investment in food hygiene, handwashing, and most recently, respiratory hygiene campaigns aimed at re-engaging the public and changing behaviour. A parallel agenda of global importance is sustainable development. Health is a fundamental human need. Improving health and life expectancy is one of the fundamental goals of society. Health is also at the heart of social sustainability. Conversely, poor health is a major drain on economic sustainability. Hygiene seeks to promote and protect health by prevention of infection. Prevention is intrinsically a more sustainable approach than treatment, which is not always successful. Of equal importance is that hygiene measures to protect health must themselves be sustainable; hygiene needs to be delivered in a way that is effective and efficient in social, economic and environmental terms. In developing and promoting public hygiene strategies, various potential impacts need to be assessed and managed appropriately: The life-cycle environmental impacts of hygiene procedures and products, including the proper assurance of safety. Concerns that the use of certain biocidal products could encourage development and spread of antibiotic resistance, and that use of biocides may lead to resistance to those biocides. The notion, based upon the hygiene hypothesis, that lack of “exposure to “infection” may be contributing to increased incidence of allergic diseases such as asthma, hay fever etc – i.e. that we are “being too clean”. Currently, within the EU, various processes are being implemented that bear on the above, notably initiatives on Sustainable Consumption and Production, the REACH Regulation (Registration, Evaluation and Authorisation of Chemicals) and the Biocidal Products Directive. There is also increasing focus on how to control the development of antibiotic resistance, and how to protect health with less reliance of antibiotics as a routine. We will also gain a better understanding of the link between microbial exposure and the development of allergic diseases. Unfortunately, each of these issues – infectious diseases, sustainability, environmental issues, product safety, antibiotic resistance and allergic diseases – tends to be addressed in isolation, often by separate agencies, such that there is relatively little opportunity to address and balance the incompatibilities and tensions between them. If we are to deliver maximum health benefit in a manner that is sustainable and to engage the public in sharing the responsibility for reducing the burden of infectious disease, and 17 its social and economic impacts, it is of paramount importance that the benefits and risks of the various measures must be properly weighed. The purpose of this report is to highlight the importance and potential of “everyday life” hygiene to contribute to a more sustainable future by reducing the social and economic burden of infectious diseases, and to propose a strategy for achieving this that is itself sustainable. The report has been prepared by the International Scientific Forum on Home Hygiene (IFH). IFH is a global, professional, non-government organisation which was established in 1997 to develop and promote an approach to home hygiene based on sound scientific principles. IFH has used the growing volume of scientific data to formulate a risk-based or ‘targeted’ approach to hygiene in the home and community that can help maximise the protection against infection. Whilst targeted hygiene was originally adopted by IFH as a means to develop an effective code of hygiene practice for the home, it also, as outlined in this report, provides a framework for ensuring sustainability of hygiene and hygiene products. 2. THE BURDEN OF HYGIENE-RELATED INFECTIOUS DISEASES IN THE EUROPEAN UNION A significant proportion of the infectious disease burden in the EU is caused by diseases that are hygiene-related (i.e. transmitted via food, water, faecal and other waste material, hands and other surfaces, and via the air). The burden of communicable diseases in Europe is summarised in a series of European Centre for Disease Control and Prevention (ECDC) annual reports.1 In the last 20 years or more, a number of events and/or trends can be identified that have necessitated investment in public hygiene promotion campaigns. These derive from the constantly changing nature and range of pathogenic micro-organisms to which we are being exposed; experience now shows that as soon as we begin to get one pathogen under control another emerges. Indications are that poor hygiene has been a contributory factor in the global spread of pathogens such as norovirus, Helicobacter pylori (H. pylori), Staphylococcus aureus, Legionella and Campylobacter, pathogens that were largely unheard of before the 1980s. The threat posed by emerging diseases such as avian influenza, SARS and swine flu has prompted the realisation that, in the event of a pandemic, hygiene is an important first line of defence during the early critical period before mass vaccination becomes available. Some of these emerging infections have been caused by species that are normally present in the environment, but have become pathogenic as a result of changes in technology (food technology, building design and operation etc) or societal changes. Other emerging infections have involved new strains of already known and wellestablished pathogens. The most recent examples include SARS, avian and swine flu, and community-acquired strains of methicillin resistant Staphylococcus aureus (MRSA). Some of these are a concern because they have developed altered or enhanced virulence properties (e.g. they have acquired the ability to produce a specific toxin, or enhanced levels of toxin). Others are a problem because they have become resistant to the action of antibiotics. Molecular and other improved technologies for detecting pathogens now show the extent to which viral agents such as the norovirus, rotavirus and adenovirus are a cause of community-acquired infections. Since viral infections are not treatable by antibiotics, this reinforces the need for prevention through hygiene. 18 The changing “hygiene climate” in the home and community not only reflects the constantly changing nature and range of pathogenic micro-organisms to which we are exposed, but also the social, demographic and other changes that are occurring within the EU which affect our resistance to infection. Trends in hygiene-related diseases are reviewed in a 2009 IFH report.2 The main findings are reviewed in this section. 2.1 INFECTIOUS INTESTINAL DISEASES Despite significant investment at all levels, food-related, waterborne, and other nonfood-related infectious intestinal diseases (IID) remain at unacceptably high levels. This is despite the efforts of food producers to ensure the safety of the food chain. A report by the European Food Safety Authority (EFSA) and the ECDC in 2007, estimated that one third of populations in developed countries are affected by foodborne diseases every year.3 The 2003 World Health Organisation (WHO) report concluded that about 40% of reported food-borne outbreaks in the WHO European Region occur in private homes.4 Preventing food-related infections relies on a combination of good hygiene practices during food preparation, cooking and storage; in theory food poisoning is 100% preventable. The potential for food poisoning at home is indicated by the prevalence of food-related pathogens in products purchased from retail premises. A 2009 EFSA report based on data reported back from EU countries in 20075 showed that Campylobacter was mostly found in raw poultry meat with an average of 26% of samples showing contamination. Poultry and pig meat were reported as the foods most frequently associated with Salmonella; on average 5.5% of fresh poultry meat samples was found to be contaminated. Chapman et al. showed that 0.4-0.8% of meat products purchased from butchers in the United Kingdom (UK) were positive for Escherichia coli O157. 6 It is now increasingly recognised that intestinal infections circulating in the community are by no means all foodborne; a substantial proportion of the total IID burden in the community is due to person-to-person spread within households, particularly for viral infections such as norovirus. Person-to-person transmission in the home can occur by direct hand-to-mouth transfer, via food prepared in the home by an infected person, or by transmission due to aerosolised particles resulting from vomiting or fluid diarrhoea. Apart from transmission by inhalation of airborne particles, these infections are preventable by good hygiene practice. National surveillance systems mostly focus on food-borne disease which means that non-food-borne cases are under-reported. The 2003 WHO report stated that, of the total outbreaks reported in Europe during 1999 and 2000, 60 and 69%, respectively, were due to person-toperson rather than food-borne transmission.4 A study of UK outbreaks7 suggested that 19% of Salmonella outbreaks and more than half of E. coli O157 outbreaks are transmitted by non-food-borne routes. Two large community studies have been carried out in Europe, one in the UK8 and the other in The Netherlands.9 The UK study, carried out between 1993 and 1996, estimated that only 1 in 136 cases of gastrointestinal illness is detected by surveillance and that, for every one reported case of Campylobacter, Salmonella, rotavirus and norovirus, another 7.6, 3.2, 35 and 1,562 cases, respectively, occur in the community. From this, it is possible to estimate the true number of infections occurring in the community (Table 1). 19 Table 1 – Estimated number of cases of infectious gastrointestinal disease in England and Wales associated with Campylobacter, Salmonella, rotavirus and norovirus Organism Number of laboratory reports from faecal isolates in 2005 Campylobacter 42,679 Salmonella 11,191 Rotavirus 13,306 Norovirus 2,607 Ratio of actual reported cases 7.6 3.2 35 1562 Estimated number of cases in the community 324,360 47,763 567,790 4,072,734 Indications are that norovirus is now the most significant cause of IID in the developed world.10 It is thought that norovirus strains now circulating are more “virulent” and more easily spread from person-to-person via hands and surfaces or during food-handling.10 Rotavirus is the leading cause of gastroenteritis in children under 5 years of age.11 The UK study indicated that as many as 1 in 5 people in the UK population develop IID each year (an estimated 9.4 million cases) of which about 50% are non-foodborne.8,12 In The Netherlands9 it was estimated that about 1 in 3.5 people experience a bout of IID each year. A 2007 report of food- and non–food-borne outbreaks in Germany13 suggested that the most common settings for outbreaks are households (53%). Of 14,566 outbreaks, 5,400 were indicated as person-to person transmission, 1637 to food, and 85 to water. Clostridium difficile-associated intestinal disease occurs with increasing frequency in the community, where it most usually affects home-based patients undergoing antibiotic or other treatment, but occasionally affects otherwise healthy individuals.14 Over 80% of cases are in the over-65 age group. Carriage rates in healthy people in the community may be around 3% to 5%.15, 16 Although there are no data to indicate what proportion are carriers of toxin-producing strains, indications are that the numbers that are toxin producers has increased.17, 18 It is estimated that, more than 13,000 cases of community-acquired infection occur each year in the UK.16 Data from Sweden indicate that 42% of cases of C. difficile infection occur in the community.19 In Ireland, 11% of cases presenting with C. difficile-related diarrhoea had no hospitalisation within the previous 60 days.20 In general, it is assumed that community water supplies in developed countries are safe with respect to microbial risks. This is not necessarily the case,21 particularly in regions of Europe where political and economic upheaval have led to infrastructure deterioration. Additionally, whereas towns and cities of Europe are generally well supplied with running water, many rural populations still rely on small private supplies, where contamination risks are higher. Water-borne disease is reviewed in more detail in a 2005 IFH report.22 Despite the fact that water quality standards are high in most European countries, outbreaks of water-borne disease continue to occur. For 1986–1996, data from 17 countries in the European region indicated a total of 2,567,210 cases of IID, 2% of which were linked to drinking water. It appears that outbreaks of water-borne diseases have been increasing in countries that have experienced recent breakdown in infrastructure, although reliable data on water quality and incidence of disease are lacking. In situations where water quality is consistently poor, or in emergency situations (e.g. where outbreaks of Cryptosporidium occur as a result of breakdowns in the water treatment or 20 distribution system) point-of-use water treatment within the home becomes the responsibility of the family, if gastro-intestinal infections are to be prevented. 2.2 RESPIRATORY INFECTIONS Recent emergent respiratory tract (RT) pathogens include viruses such as SARS, avian and swine flu. Until quite recently, it was generally thought that transmission of RT infections was almost entirely by the air-borne route, involving aerosols (small <10 droplet nuclei) or droplets generated by coughing and sneezing.23 Although, supporting data related to colds have been available for some time, it is only in the last 5 to 6 years that there has been any real awareness that not just coughs and sneezes, but also hand and surface hygiene play a part in reducing the spread of not only colds but also influenza.24, 25 Although colds are generally mild and self-limiting, secondary infections produce complications, such as otitis media, sinusitis, or lower respiratory infections such as pneumonia, which require hospitalisation and have high risk of mortality, particularly in the elderly and other risk groups.26 Several studies have demonstrated that colds are also a trigger for asthma.27 Influenza, is a more serious RT illness which can cause hospitalisation and death, the risks being highest among persons aged >65 years, children aged <2 years, and persons who have medical conditions (e.g. diabetes, chronic lung disease).28,29 Colds and influenza must also be considered in terms of days absent from work and school, and costs to healthcare services.29 The incidence of influenza in EU countries is reviewed in the 2009 ECDC communicable diseases report.1 A major concern is the emergence of novel subtypes capable of causing an influenza epidemic or pandemic.30 Since new strains arise every 1 to 2 years, there is no lasting immunity against influenza, neither after infection nor after vaccination.30 Across the world, preparations for the next influenza pandemic started in 2005. Hygiene is seen as being important as a first line of defence to mitigate spread during the early critical period before mass vaccination becomes available. 'Global Preparedness' means that respiratory hygiene needs to become part of our daily lives already before such an event. If the public are to play their part, however, knowledge and awareness of these personal measures needs to be improved.31 Legionella infections are also known to be domestically acquired.32 In Germany 47% of notified infections are estimated to be acquired at home.33 Surveys in Italian houses indicate that Legionella contamination of domestic hot water ranges from 22.6% of samples from a countrywide investigation34 to 41.9% of samples obtained from 59 apartments in Bologna.35 2.3 SKIN INFECTIONS - STAPHYLOCOCCUS AUREUS AND MRSA Skin and wound infections are common in the home and community. S. aureus is the most common cause of skin and soft tissue infections, which are mostly self-limiting, but a small proportion of cases leads to severe invasive bacteraemias or pneumonia.36 Between 30% and 60% of the general population37 carry S. aureus as part of their normal body flora38. A UK study39 indicates a major increase in pathogenic community-onset staphylococcal disease over the past 15 years. It was found that hospital admission rates for staphylococcal septicemia, pneumonia, impetigo etc increased >5-fold. It was postulated that this trend may be partly due to changes in hygiene behaviour. Of particular concern are the antibiotic resistant strains of S. aureus (MRSA). MRSA in the home and community was reviewed in a 2006 IFH report. 14 This report shows 21 how problems related to MRSA are by no means confined to the hospital setting. Infected patients discharged from hospitals may continue to carry MRSA, even after their infection has healed, and pass it on to healthy family members who become colonised, thereby spreading the organism into the community. Healthcare workers caring for MRSA-infected hospital patients may also bring MRSA back into the home on their hands or uniforms etc. MRSA has the same potential to infect the elderly and immuno-compromised in a home setting whilst family members who are MRSA carriers are at increased risk of infection following hospital admission or outpatient treatments. A new concern, also reviewed in the IFH report,14 is the emergence of new “community” strains of MRSA (community-acquired MRSA or CA-MRSA). Whereas healthcare associated (HCA) MRSA strains are mainly a risk to vulnerable people, for CA-MRSA any family member is at risk, although US experience suggests that CAMRSA strains present a threat mainly to those engaging in activities involving close skin contact and abrasion such as sports clubs and schools. Some S. aureus strains circulating in the community [both CA-MRSA and methicillin sensitive S. aureus strains (MSSA)] strains have also acquired the ability to produce Panton-Valentine Leukocidin (PVL) toxin. These can cause severe invasive infections such as bacteraemia, or necrotising pneumonia that kills more than 40% of patients. Although CA-MRSA strains are now a major problem in the USA,40 they are still relatively uncommon in Europe, and there is thus still an opportunity to avoid the problem escalating to a similar same scale. CA-MRSA strains are already reported in UK, France, Switzerland, Germany, Greece, Ireland, Nordic countries, Netherlands and Latvia.41 Establishing the prevalence of MRSA circulating in the general community is difficult and can vary significantly from one area to another. Establishing which cases are healthcare-associated strains and which are “true” de novo community-acquired strains is also difficult. In the UK, indications are that the proportion of the general population carrying antibiotic-resistant strains of S. aureus (either HCA or CA-MRSA) is somewhere between 0.5% and1.5%. The prevalence of PVL-producing strains circulating in the UK community is currently small;42 perhaps around 2% of UK MRSA strains are PVL-positive, but the figure may be much higher. Data presented in the 2006 IFH review on MRSA14 shows that good hygiene is important not only in protecting at-risk groups cared for at home, but also containing the circulation of CA-MRSA and HCA-MRSA in the community. A number of case studies are reviewed which showed that MRSA carriage in healthcare workers could only be eliminated if skin decontamination was combined with a rigorous hygienic cleaning programme aimed at eliminating MRSA from their home environment. 2.4 FUNGAL INFECTIONS Fungi in indoor environments are a potential problem. They can be responsible for infections, cause allergic responses, deteriorate/damage surfaces and cause unpleasant odours. Moulds produce millions of spores, which, due to their small size (average size 1–5 m) easily stay air-borne and may be breathed deep into the airways. Air-borne fungi are usually associated with damp conditions, poor ventilation or closed air systems. Primary sites of fungal growth are inanimate surfaces, including carpets and soft furnishings.43 Some fungi are pathogenic to healthy humans, causing superficial infections (mycoses), where the fungus grows on body surfaces such as the feet, skin, hair and 22 nails, as well as the oral or vaginal mucosa. They are spread by direct contact and are highly contagious and easily spread to other individuals. Infections within the body (deep mycoses) are rare in healthy humans but people with impaired immune functions (e.g. cancer patients receiving chemotherapy or people with AIDS) are at significant risk. They can be acquired by inhalation of spores or by entry through wounds.44,45 Fungal infections in the home and the role of hygiene in preventing the spread of fungal infections are described in more detail in a 2004 IFH review 46 and a review by Scott.47 2.5 ANTIBIOTIC RESISTANCE Antibiotic resistance is a major threat that severely undermines our ability to control infectious diseases. The implication is that greater emphasis must now be placed on preventive strategies such as hygiene, rather than reliance on antibiotic therapy, and that these strategies need to be developed not only in hospitals but also in the community. A number of aspects need consideration. Firstly, hygiene is recognised as a strategy per se for reducing antibiotic resistance. Good hygiene means fewer patients with infections demanding antibiotics from their GP, thereby reducing the selective pressure that drives the ongoing emergence of antibiotic-resistant strains. The benefits of this approach have been demonstrated in clinical settings.48,49 The second aspect, as discussed in section 2.3, relates to the spread of pathogens such as MRSA and ESBLs (extended spectrum lactamase-producing E. coli) in the home and community. Good hygiene is key to protecting risk groups, cared for at home, from infection including with antibiotic-resistant strains of opportunist pathogens such as HCA-MRSA and ESBLs. Circulation of resistant strains in the community has important implications for delivering infection control in hospitals. Hospital managers now realise that managing healthcare-associated infections is hampered by people (new patients, visitors and healthcare workers) who are “silent” carriers of resistant organisms such as MRSA, ESBLs, (and also C. difficile) that walk into their facilities. By preventing the spread of these organisms through better hygiene, we can reduce the reservoir of antibiotic-resistant strains circulating in the community, which means that the opportunities for their introduction into hospitals via new patients, healthcare workers and hospital visitors is reduced. The need for improved hygiene to reduce the spread of antibiotic resistance was first addressed in the 1999 report of the EU Scientific Steering Committee entitled “Opinion on Antimicrobial Resistance”.50 The report stated that “there should be action to reduce the risk of infection in individuals and in the population as a whole by encouragement of uptake of immunisations, education regarding home hygiene, attention to public health issues, and by the maintenance and/or improvement of housing and social conditions”. The key action points set out by ECDC in their initiative on antibiotic resistance are “using less antibiotics” and “preventing the spread of antibiotic-resistant strains between people”.51 Educating primary and secondary school pupils about antibiotic resistance and hygiene is the fundamental aim of the EU-sponsored e-Bug project.52 This is a Europe-wide project that aims to ensure that all children will leave school with knowledge of prudent antibiotic use and how to reduce spread of infections for themselves and their children through hygiene. 23 2.6 PETS AND DOMESTIC ANIMALS AS A SOURCE OF INFECTION IN THE HOME In the English-speaking world more than 50% of homes have cats and dogs. Domestic cats and dogs can act as reservoirs of Salmonella, Campylobacter and other enteric pathogens.53,54,55,56,57 Domestic animals can also be a source of S. aureus, including MRSA and PVL-producing strains.58,59,60,61 Carriage of C. difficile in household pets is common; 62 up to 23% of household pets are affected, although carriage appears to be transient and not associated with IID. The increasing popularity of exotic pets also increases the risk of humans acquiring zoonotic infections.63 Although there is significant evidence that domestic pets have the potential to act as a source of infection in the home, there are few data indicating the extent to which this may or may not occur.64,65 In a study of 50 US homes where children under 4 years were known to be infected with Salmonella spp., in 34% of homes there was also found to be illness in other family members.66 It was found that environmental sources, infected family members and pets, were more significant risk factors for development of salmonellosis than contaminated foods. Two further studies describe discharged hospital patients and healthcare workers who were successfully treated at home to eradicate MRSA carriage, but subsequently became recolonised. 58,59 Further investigation suggested that the source of re-colonisation was a domestic dog. In a study carried out in the USA in 2006, 35 homes were recruited from the Boston area. S. aureus was found in 34 of the 35 homes. MRSA was isolated from 9 of 35 homes, and was found on a variety of household surfaces. A positive correlation was indicated for the presence of a cat and the isolation of MRSA from surfaces.67 2.7 AT-RISK GROUPS IN THE HOME AND COMMUNITY The changing “hygiene climate” in the home and community not only reflects the constantly changing nature and range of pathogenic micro-organisms, but also the social, demographic and other changes that are occurring within the global population which affect our resistance to infection. Demographic changes and changes in health service structure mean that the number of people in the home needing special care, because they are at greater risk of infection is increasing. The largest proportion is the elderly who have reduced immunity to infection, which is often exacerbated by other illnesses such as diabetes, etc. Risk groups in the home also include the very young, patients discharged recently from hospital, and family members with invasive devices such as catheters. It also includes people whose immuno-competence is impaired, either as a result of chronic and degenerative illness (including those who are infected with HIV/AIDS), or because they are undertaking certain drug or other therapies. This includes those undergoing irradiation or chemotherapy for cancer, and organ transplant recipients. Immunosuppressed persons are often also on other medications such as antibiotics, which can further increase their susceptibility to infections.68 Data collected from several European countries suggest that at up to 1 in 5 of the population belongs to an “at-risk” group (Table 2). The data suggest that between 12% and 18% of the population of these countries are >65 years of age. 24 Table 2 – Prevalence of “at-risk” persons in the domestic setting. Total population Over 65 years old Living with cancer – significant proportion undergoing chemotherapy Under 1 year old Discharged from hospital within previous 2 weeks Hospital outpatients at home HIV cases* AIDS cases Total “at risk” persons UK (2002) 60 million 9 million Germany (2002) 82 million 13 million 1 million 600,000 200,000 Holland (2002) 16 million 2 million Russia (2003) 145 million 16 million Ukraine (2003) 50 million 14 million 1.3 million 400,000 177,000 500,000 >1 in 8 >1 in 3 160,000 800,000 100,000 60,000 1, 270,000 50,000 15,000 >1 in 6 >1 in 5.6 >1 in 6.3 *This does not include those who are HIV positive who may also have lowered resistance to infection The elderly are at increased risk of death from gastro-intestinal disease.68 Problems of faecal incontinence create an environment in which enteric and food-borne pathogens are easily spread. Incidence of salmonellosis and Campylobacter diarrhoea appears to be higher among the elderly. Data from the US68 suggest increased case rates for Campylobacter and listeriosis among persons with AIDS, as compared with the general population. An estimated 10–20% of cases of AIDSassociated diarrhoea are due to the waterborne pathogen Cryptosporidium.69 Cancer cases have steadily increased in the past 20 years. Cancer patients undergoing immuno-suppression therapy have higher risk rates of septicaemia and food-borne infections.68 The number of people in the community living with organ transplants is also increasing. Increased survival rates have been achieved by the use of cyclosporine and other immune-suppressants but these in turn prevent the immune system from reacting to infectious agents. According to the USA United Network of Organ Sharing, approximately 15% of all deaths in transplant recipients are a result of infection in the first 3 months.70 Across Europe, governments are increasingly under pressure to fund the level of healthcare that people expect. Care of increasing numbers of patients in the community, including at home is one answer, but can be fatally undermined by inadequate infection control in the home. Increasingly, all of these “at-risk” groups are cared for at home by a carer who may be a household member who thus requires a good knowledge of hygiene. 2.8 THE IMPACT OF SOCIAL DETERMINANTS ON THE SPREAD OF INFECTIOUS DISEASES Across Europe, there is an inequitable distribution of communicable diseases. Populations at higher risk of infection in Europe coincide with those with a low level of education, occupational class, or income level. These sub-populations suffer disproportionately from a range of infections, including H. pylori, respiratory infections, sexually transmitted diseases, and nosocomial infections. In low-income populations, malnutrition also contributes to increased susceptibility to infection. 25 These factors can initiate a “vicious cycle” of infection predisposing to malnutrition and growth faltering, which in turn leads to increased risk for further infection. The self-perpetuating cycle leads to adverse health effects with differential consequences because of poor access to care. The "vicious cycle" can result in a descent down the socio-economic ladder, because healthcare costs and loss of work disproportionately affect disadvantaged groups. The impact of social determinants on the incidence and prevalence of communicable diseases in the newly expanded EU is discussed in a 2008 review by Semenza and Gieseke.71 They concluded that “unless the fundamental causes of disease, namely the social determinants of health, are improved, disparity in health outcomes will not be ameliorated”. 2.9 THE IMPACT OF SOCIAL TRENDS ON THE SPREAD OF INFECTIOUS DISEASES Trends in social behaviour, eating habits, availability and use of home appliances etc are also increasing the risks of transmission of infectious diseases in the home. The demand for different and “exotic foods” stimulates increasing movement of foodstuffs from one region or country to another and creates problems in controlling microbial quality.63,72 Increasing population global mobility means that, as in the case of SARS, virulent pathogens can move rapidly across the world, making it difficult to contain epidemics related to novel strains. In “westernised” homes, knowledge and skills in food handling and preparation have declined with increasing reliance on refrigerators, freezers, microwave ovens and dishwashers.63 In some cases, misuse of appliances contributes to the risks of infection. The threat of listeriosis has increased with increasing use of refrigerators because L. monocytogenes can multiply on certain types of foods even at refrigeration temperatures.73 In the past few years, there has been a steady increase in the use of microwave ovens in the home without proper appreciation that microwaving may not make foods safe.74,75,76 Although, hygiene of dishes and utensils has improved with the use of dishwashers, they are not universally used, and water temperatures for washing dishes have declined. Although manually washed eating utensils are normally wiped dry or left to air dry, which can inactivate microbial pathogens,77 cross contamination can occur if contaminated water or contaminated dish rags or sponges are used for washing or drying.78 Clothing, bed linens, towels and other items that are in contact with the body may be a vector for transmission of infection. Cross contamination by household laundry has been demonstrated by a number of studies.14, 79 Of current concern is the potential for spread of S. aureus, particularly community-associated MRSA strains via clothing and towels. Domestic clothes-washing practices have changed in the past 3 decades to achieve energy conservation, but with little attention to the possible implications for hygiene. Kniehl et al.80 described a study in Germany, of healthcare workers who had regular close contact with MRSA-colonised patients. Sampling detected contamination in 7/8 home environments affecting pillows, bed linen, brushes and hand contact surfaces. Little is known about how well low-temperature washing techniques eliminate pathogens from clothing and prevent cross contamination between laundered items. A new study by Exner and co-workers is discussed in section 3.2. Heating and air conditioning systems mean that windows are often sealed, air is recycled, and ducting can accumulate dust or act as a site for microbial growth. Mechanical heating or air cooling can alter humidity, which can influence air-borne survival of pathogens.81 Allergens and endotoxins produced by some bacterial and fungal agents are increasingly implicated as causes of disease in humans.82 26 Legionnaires’ disease is an example of how conditioning of indoor air has turned an environmental bacterium into a human pathogen. 2.10 CHRONIC SEQUELAE OF INFECTIOUS DISEASES Whereas there has been a tendency to assume that common gastro-intestinal, respiratory and skin infections circulating in the community are a relatively minor concern, data increasingly show that both intestinal and also respiratory pathogens can act as co-factors in diseases such as cancer and chronic degenerative diseases, or as triggers for the development of allergic diseases. This further supports the need to better control the spread of these diseases. Examples include Campylobacter jejuni (Guillain Barré syndrome)83 and H. pylori (cancer).84 Clusters of Campylobacter infections are known to arise in family households, and complications such as Guillain Barré syndrome are a real concern.85,86 Food-borne illness has been estimated to result in chronic sequelae in 2–3% of cases.87 A report from the European Commission88 cited evidence of chronic disease, such as reactive arthritis, following 5% of Salmonella cases, with 5% also of E. coli O157 cases progressing to the serious and often fatal complication of uraemic syndrome. Viral respiratory infections, even mild infections, can be important predisposing factors to more severe and possibly fatal secondary bacterial infections.89 There is also growing evidence that respiratory viruses may exacerbate attacks of asthma.90,91,92 Recurrent wheezing in children has been associated with respiratory infections early in life, RSV being one of the main viral agents thought to be responsible.93,94 A study of the influence of childhood respiratory infections on adult respiratory health95 suggests that the impact may not only last into adulthood but also influence development and persistence of adult respiratory morbidity. Richardson et al. present evidence that suggests that enteroviruses may be a trigger for type 1 diabetes.96 Other studies show that infection may be more significant in sudden unexpected death in infancy (SUDI) than previously thought.97,98,99,100 A UK retrospective study of post-mortem data on 546 cases showed that S. aureus and E. coli were more common than expected in babies whose deaths could not be explained.97 3. DEVELOPING A RISK-BASED APPROACH TO HOME HYGIENE The IFH (www.ifh-homehygiene.org) was established in 1997 in response to concerns about the need for an international body that could speak from a scientific/medical standpoint about home and community hygiene. The aim of IFH is the development of an evidence-based approach to home hygiene, and the promotion of this approach to scientists, opinion-formers, policy-makers and community health professionals. As part of this work, IFH has developed an approach to home hygiene based on risk management.24,101,102 Applied to the home, the risk-based approach has come to be known as 'targeted hygiene'. Risk management is the standard approach for controlling microbial risks in food and other manufacturing environments, and is becoming accepted as the optimum means to prevent such risks in home and hospital settings.103,104 27 3.1 IDENTIFYING CRITICAL CONTROL POINTS IN THE CHAIN OF INFECTION TRANSMISSION IN THE HOME Targeted hygiene starts from the principle that pathogens are introduced continually into the home, by people (who may have an infection or may be asymptomatic), contaminated food and domestic animals, but also sometimes in water, or via the air. Additionally, sites where stagnant water accumulates such as sinks, toilets, waste pipes, or items such as cleaning or face cloths readily support microbial growth and can become primary reservoirs of infection, although these are mostly bacterial species which only represent a risk to vulnerable groups.105 In many homes, there will also be at least one family member who is more susceptible to infection for one reason or another. Within the home, there is a chain of events, as described in Figure 1, which results in transmission of infection from its source to a new recipient. The simple principle is that, if we can break the chain of infection transmission, infection cannot spread. Fig 1 – Chain of infection transmission in the home Risk assessment is based on assessing the microbiological data related to each stage of the infection transmission cycle in order to identify the critical control points for preventing spread of infection. To identify these points, the frequency of occurrence of pathogenic contamination at individual sites and surfaces is assessed, together with the probability of transfer from that site such that family members may be exposed. This means that, even if a particular site or surface is highly contaminated, unless there is significant probability of transfer from that site, the risk of exposure is low. The risk-based approach to home hygiene is described in more detail by Bloomfield and Scott.106,107 They suggest that sites and surfaces in the home should be categorised into four main groups: reservoir sites, reservoir/disseminators, hands and hand and food contact surfaces and other surfaces. From this it is possible to determine the “critical control points” for preventing spread of infection. The data suggest that: 28 For hands, and hand contact and food preparation surfaces, although the probability of high counts of pathogens or potential pathogens is, in relative terms, less than for wet sites such as toilets and cleaning cloths, there is still a significant probability of pathogenic organisms being present, particularly, for example, following contact with contaminated food, people, pets or other contaminated surfaces such as door-, faucet- and toilet-flush handles. Since there is a constant risk of spread from these surfaces, hygiene measures are important for these surfaces. For reservoir sites such as wet cleaning cloths (reservoir/disseminators), not only is there high probability of significant contamination, but, by the very nature of their usage, they carry a high risk of disseminating contamination to other surfaces and to the hands. For reservoir sites such as toilets, although the probability of contamination (potentially pathogenic bacteria or viruses) is high, the risk of transfer is limited unless there is a particular risk situation (e.g. a family member with enteric infection and fluid diarrhea, when toilet flushing can produce splashing or aerosol formation that can settle on contact surfaces around the toilet).105,108 For floors, walls, furniture etc risks are mainly due to pathogens such as S. aureus and C. difficile that survive under dry conditions. Because the risks of transfer and exposure are relatively low, these surfaces are considered low risk, but where there is known contamination, for example, soiling of floors by pets, crawling infants may be at risk. Cleaning can also re-circulate dust-borne pathogens onto hand and food contact surfaces. This approach allows us to rank sites and surfaces (Figure 2) according to the level of risk; this suggests that the critical points are the hands, together with hand and food contact surfaces, cleaning cloths and other cleaning utensils, which form the 'superhighways' for spreading pathogens around the home such that healthy family members or the food they eat become exposed. Fig 2 – Ranking of sites and surfaces in the home based on risk of transmission of infections Although this is a useful rule of thumb ranking, it is not constant and varies markedly at different times and according to circumstances. Toilets were invented for the purpose of dealing with human waste, but this does not mean that they are zero-risk areas, they still have risks associated with them, particularly when someone in the home has sickness, diarrhoea, or other contagious infections. Although floors, however dirty they may appear, are assessed as relatively low risk, the risks increase where a pet animal and a small child share a floor area, or where a floor surface is contaminated with vomit or faeces. 29 3.2 APPLYING HYGIENE PROCEDURES TO BREAK THE CHAIN OF INFECTION IN THE HOME Targeted hygiene also means applying a suitable hygiene procedure at appropriate times to interrupt the chain of infection transmission. It is known that, even for healthy family members, the infectious dose for some enteric and respiratory pathogens, particularly viruses, can be very small (10-100 viable units or even less for some viruses) and that infection can result from direct transfer from surfaces via hands or food to the mouth, nasal mucosa and conjunctiva. Although the infectious dose for enteric pathogens such as Salmonella is generally higher (up to 106 viable units), in some situations it may be relatively low (<100 viable units). (see Bloomfield et al24 for more details on infectious doses). On this basis one must argue that, in situations where there is risk, a 'hygienic cleaning' procedure should be used which eliminates as many organisms as possible from critical surfaces. Hygienic cleaning can be done in one of two ways: By mechanical removal involving soap or by detergent-based cleaning with rinsing. In this process, soap or detergent is used to maximise detachments of microbes from the surface, whilst the rinsing process removes the organisms from the surface. To be effective this process must be accompanied with thorough rinsing under running water that is disposed of safely from the home (e.g. into the public wastewater system) such that pathogens cannot be further disseminated around the home.109,110,111 By using a process or product that inactivates the pathogens in situ. This can be achieved using a disinfectant product (such as a disinfectant or waterless hand sanitizer) or by application of heat, UV irradiation etc. Heat is an effective means of eliminating contamination from surfaces, either alone or in combination with a chemical agent. Alternatively a combination of germ removal with kill can be used. For example, to ensure elimination of pathogens, clothing and household linens should be laundered at 60ºC. Alternatively this can be achieved at 40ºC using a bleachcontaining laundry product.112 Domestic dishwashers employ a combination of heat and detergent-based cleaning with rinsing to decontaminate cooking and eating utensils. A whole range of laboratory and in use studies have been carried out to evaluate the effectiveness of hygiene procedures used in the home. These are reviewed in detail in an IFH report.113 The following examples are used to illustrate recent “in use” studies to evaluate hygiene procedures used in food hygiene, in prevention of norovirus cross infection and in elimination of MRSA from clothing and linens during laundering. 3.2.1 Hygiene procedures to prevent cross contamination during food preparation In a study on cross contamination in the domestic kitchen,114 20 participants prepared a meal using chickens naturally contaminated with either Salmonella or Campylobacter. During preparation of the chicken (Table 3), contamination was spread to the hands, hand and food contact surfaces, and cleaning cloths with a total of 17.3% of the surfaces showing evidence of the target strain. In the second part of the study, participants were instructed to clean up before sampling, using a typical detergent-based procedure using a washing-up bowl. This process produced no significant overall reduction in the incidence of contamination, the frequency occurrence of contamination on hand and food contact surfaces remaining at 15.3%. There was some reduction in contamination on hands and chopping boards, but this 30 was accompanied by an increase in contamination on some hands contact surfaces, indicating that the contamination was actually spread via the cleaning cloth during the cleaning process. In the final part of the study, disinfectant was used in addition to detergent-based cleaning. Using this procedure, there was a significant reduction in microbial risk; after cleaning with detergent and wiping surfaces with a cloth soaked in hypochlorite disinfectant (5000 ppm available chlorine) the number of contaminated surfaces was reduced to 2.3%. Table 3 - Contamination of surfaces after preparation of a meal with a chicken contaminated with Salmonella or Campylobacter, and after cleaning and disinfection Percentage of sites contaminated with Salmonella and/or Campylobacter No of participants in each After meal After cleaning with After cleaning with group = 20 preparation soap and water soap and water + hypochlorite Chopping board 60 15 0 Utensils 5 25 5 Hands 35 20 0 Dishcloth 25 25 5 Sink surround 30 30 0 Sink rim 10 15 5 Taps, Fridge, Cupboard, Oven 9 8 1 and Kitchen Door, Condiments TOTAL 17.3% 15.3% 2.3% In a follow-up study,115 using the same methodology (Table 3), the effectiveness of the “bowl washing procedure” was compared with a hygienic cleaning procedure which involved cleaning with detergent followed by rinsing under clean running water for 10 seconds. In this study surface samples were analysed to determine the number of organisms that could be recovered. In this study the key surfaces (hands, cloths, chopping board, utensils, tap handles) were evaluated. In the first part of the study, where no cleaning was performed, it was found that, respectively, 8.3% and 50% of samples taken after meal preparation showed counts of Salmonella and Campylobacter exceeding 100 colony forming units (cfus) per sample area, with 3.3% and 33% of sites showing counts of >1000 cfu. A significant reduction in the risk of contamination could be achieved where surfaces were cleaned using a detergentbased bowl wash routine followed by rinsing under running water (as compared with detergent-based cleaning alone). For Campylobacter, bowl washing with rinsing was sufficient to reduce the number of contaminated sites to 1.7% with no sites showing greater than 100 cfu. For Salmonella, on the other hand, following bowl wash with rinsing 16.7% of 60 sites sampled still showed contamination, with 3.3% of sites showing counts of greater than 100 cfu. 31 Table 4 - Viable counts on surfaces after preparation of a meal with a chicken contaminated with Salmonella or Campylobacter, and after cleaning and disinfection Cumulative % frequency occurrence of viable counts (colony-forming units per total surface sample are or 200cm-2 of cloth) >1 >100 >1000 Salmonella- contaminated chicken Before cleaning 55 8.3 3.3 After bowl washing 40 13.3 8.3 After bowl washing +10 16.7 3.3 1.7 seconds rinsing Campylobacter-contaminated chicken Before cleaning 83.3 50 33 After bowl washing 13.3 5 1.7 After bowl washing +10 1.7 0 0 seconds rinsing As a follow-up109 Barker et al. developed a laboratory model using chickens artificially contaminated with Salmonella enteritidis PT4, to confirm the effectiveness of detergent-based and disinfection procedures as determined previously with naturally contaminated chickens. In this study, hygiene procedures were assessed on the basis of their ability to reduce the number of recoverable salmonellas to <1 cfu. Although detergent-based cleaning using a bowl-wash routine without rinsing produced some reduction in risk (from 100% to 61.4% of contaminated surfaces), it was insufficient to consistently restore surfaces to a hygienic state. By combining detergent-based cleaning with a rinsing step or with hypochlorite at 500 ppm (of available chlorine) some further reduction in microbial risk was achieved, but was not considered satisfactory for food hygiene purposes. By contrast, the risk reduction produced by hypochlorite at 5000 ppm was highly significant and was sufficient to reduce the number of contaminated surfaces to 2.9%. The extent of the risks associated with inadequate hygiene cleaning of hands, hand and food contact surfaces during food preparation in the home is indicated by data taken from other sources. A 2007/8 survey carried out by the UK Food Standards Agency showed that up to 6.6% and 65.2% of chickens bought from retail premises are contaminated with Salmonella and Campylobacter, respectively.116 As stated previously, an EFSA report based on data reported back from EU countries in 2007 reported that, in foodstuffs, Campylobacter was mostly found in raw poultry meat with an average of 26% of samples showing contamination. Poultry and pig meat were reported as the foods most frequently associated with Salmonella, and on average 5.5 % of all fresh poultry meat samples was found to be contaminated. For the UK, the stated contamination rates mean that around 1 in 25 UK homes prepares a meal using a Salmonella- or Campylobacter-contaminated chicken every day. It has been shown that contamination transferred to surfaces can survive for at least 4 hours up to 24 hours for Salmonella.24 The infectious dose for Campylobacter is of the order of 100-500 cells72 whilst for Salmonella it may be as much as 106 cells, but may be as little as 10 cells.117 A 2001 study of 192 food-borne outbreaks linked with private residences in England and Wales suggested that cross contamination is a factor in about 10% to 20%.118 The estimate from the community-based study of IID in England and Wales is that the annual number of cases of Salmonella and Campylobacter infection in the community is of the order of 400,000.8 In 2007, 204,104 cases of campylobacteriosis 32 were reported by 25 EU member states, and 157,739 cases of Salmonella were reported by all EU and Euroean Club Association (ECA)/European Free Trade Association (EFTA) states.1 It is likely however that the actual number of cases is much higher. Taken together the data from the studies described in this section suggest that a significant reduction in the number of cases of food poisoning could be achieved by targeted use of an effective disinfectant product during handling of raw foods such as poultry. 3.2.2 Hygiene procedures to prevent spread of norovirus between family members A study by Barker et al.110 shows the ease of spread of norovirus from environmental surfaces via hands, cloths and other surfaces. In this study a small sample of a faecal suspension from a person infected with norovirus was placed on a surface to simulate a typical situation where there is an infected person in the home. The presence of residual norovirus on surfaces was detected by RTP-PCR (Reverse Transcriptase Polymerase Chain Reaction). The study showed that where contaminated surfaces were cleaned using detergent and water applied with a cotton woven cloth, on every occasion (the experiment was repeated 14 times), the virus was not eliminated from the surface, and when the cloth was used to wipe another clean surface, the virus was transferred to that surface and to the hands of the person handling the cloth. Detergent-based cleaning was insufficient to eliminate norovirus and prevent transfer, even where the cloth was rinsed out in clean water and the surface re-wiped. In order to eliminate the norovirus from the cloths and surfaces, it was necessary to use a hypochlorite disinfectant containing 5000 ppm available chlorine. In situations where there was faecal soiling, it was necessary to clean with detergent before application of disinfectant. Data suggest that, where an infected person has fluid diarrhoea or vomiting, the virus can be spread via aerosols generated by toilet flushing which can settle on surfaces in the toilet such as the toilet seat, basin and toilet flush handle or by the settling of particles of vomit on surfaces.105,108 It is known that a single vomiting incident can produce 30 million norovirus particles.119 Other studies show that norovirus can remain viable on these surfaces for several days and that the infectious disease associated with hand to mouth transfer can be as little as 6-10 virus particles.119 In the UK, it is estimated that about 4 million cases of norovirus occur annually. About 97% of these cases involve person to person rather than food borne transmission. Overall this suggests that a significant reduction in the spread of norovirus from an index case in the home could be achieved by good hand hygiene and targeted use of an effective disinfectant product on critical contact surfaces. 3.2.3 Hygiene procedures to prevent transmission of MRSA via clothing and household linens As stated in section 2.8, domestic clothes-washing practices have changed significantly in the past 3 decades. One of the driving factors has been to achieve energy and water conservation, but with little attention to the possible implications for hygiene. As discussed in section 2.3, in the USA, CA-MRSA is now a significant concern. Although rates of colonisation in the community are still low, it is nonetheless thought to be increasing.120, 121,122 A study of patients with skin and soft tissue infections seeking treatment at a Los Angeles emergency department reported that the proportion of CA-MRSA cases increased from 29% in 2001 to 2002 to 64% in 2003 to 2004.123 A review of 1063 children 0 to 18 years old conducted by a Rhode Island Hospital between 1997 and 200 showed that both the absolute number of 33 MRSA cases and the proportion of S. aureus cases due to MRSA rose more than threefold. Of 57 MRSA cases, 23 (40%) were CA-MRSA.124 As stated in section 2.3, although CA-MRSA strains have been detected in many European countries, there is still an opportunity to avoid the problem escalating to a similar same scale in Europe as in the USA. Experience in the USA suggests that CA-MRSA is easily transmissible within families and community settings such as schools and sports teams. Skin-to-skin contact (including intact skin) and indirect contact with contaminated objects such as towels, sheets and sport equipment are the primary vehicles of transmission.125 A study of US homes by Scott et al. showed that MRSA could be isolated from a variety of frequently touched surfaces (including wiping cloths and dishtowels) in 9 out of 35 homes.67 In German homes where there is a carrier, MRSA has been isolated from laundered items (personal communication from Martin Exner, May 2001). In a 2009 study (Exner personal communication), Exner and co-workers studied the hygiene effectiveness of machine laundry processes on cotton samples artificially contaminated with S. aureus. Results (Table 5) showed that although premium detergent cycles at 40°, 60° and 80° C produced an 8 log reduction in contamination without the need for a pre-wash programme, cycles at 30° C produced only a 6 log reduction with pre-wash and only a 3 log reduction without pre-wash. With nonpremium detergents (liquid colour detergent and gel detergent) cycles, although 60°C cycles produced greater than 4 log reduction, 30°C cycles, even with pre-wash, produced less than 1 log reduction, With 30°C and 60°C temperature cycles used with non premium detergents there was also cross contamination between contaminated and sterile laundry samples that were included in the cycle. Where samples washed at 30°C with universal detergent were dried for 24 hours at room temperature there was little or no increase in log reduction. Taken together, these data indicate the importance of ensuring that recommended laundry processes deliver hygiene using appropriate combinations of removal and microbial kill. Table 5 - Disinfection of laundry samples inoculated with S. aureus in the main cycle machine washing programmes. The study was carried out using the DGHM (German Society for Hygiene and Microbiology) standard method.126 Pre-wash Temperature No 80°C No 60°C No 40°C No 30°C Yes Washing agent Premium washing pearls (contain a bleaching agent based on oxygen and an optical brightener) Mean Log 10 Cross contamination Reduction to sterile cloth sample Factor included in cycle 8.15 No 8.18 No 8.06 No 3.07 No 30°C 6.31 No No 60°C 4.22 no Yes 60°C 6.99 Yes No 30°C ≤1 Yes Yes 30°C ≤1 Yes No 30°C 1,75* Yes No 30°C 2,09** Yes Liquid colour detergent (contain optical brightener only) Universal gel detergent (contain optical brightener only) * wet cotton cloths; ** dried (24 h) cotton cloths 34 Even today, there is still a body of expert opinion, which holds to the view that, in home and everyday life environments, soap and water are all that is required, there is no need for the use of biocidal hygiene products. This recommendation makes no reference to how soap/detergent-based processes should be applied in order to be effective, and makes the assumption that the process is consistently effective. It also takes no account of the data showing that, in reality, soap and water can be a very effective means of spreading contamination from one surface to another. Overall the data presented above, together with other data presented in the IFH review of home hygiene procedures,113 clearly show that, in some situations, soap and water alone are insufficient to eliminate contamination from critical control points. In these situations it is necessary to use a process, such as the application of an effective biocide, a waterless hand rub, or the use of heat, UV irradiation or other process that can inactivate microbes in situ. One of the arguments put forward against the use of biocidal hygiene products is that although the germ removal by cleaning alone is less than that which can be achieved by the use of biocidal products and processes, it is sufficient to produce hands, surfaces, fabrics etc which can be considered as safe i.e. for which the level of residual germs are no longer a threat to health. However, data increasingly show that the infectious dose for many common pathogens, particularly viruses, but also bacteria, can be very small, and that for pathogens such as Salmonella transferred to food, a very small number of cells can multiply rapidly during storage at room temperature to produce levels that are infectious. It also takes no account of the fact that a substantial proportion of “healthcare”, the care of at-risk groups, now takes place in the home, much of it provided by family members. The benefits of maximising germ removal from critical surfaces has been demonstrated by application of quantitative risk modelling techniques to hand hygiene. A study by Haas and co-workers127 showed that, although the benefit of using an alcohol hand rub which increases the log reduction on hands is not measurable in terms of the individual, this can translate into a significant decrease in disease burden within a community of individuals. In this study, data from the literature were used to model transfer of E. coli O157:H7 from hand-to-mouth following hand contact with ground beef during food preparation. Assuming that there are 100 million individuals in the USA each of whom handles ground beef once per month, and that 10% of these individuals contact hand-to-mouth after handling ground beef, this amounts to 120 million infection incidents per year. From the microbiological data on the typical levels of contamination of E.coli found in raw meat, rates of transmission etc, it was assessed (Table 6) that if all individuals washed their hands with soap following contact with ground beef (median log reduction on hands assessed as 0.3) this would result in an estimated 0.014 infections per year. If, on the other hand, individuals used an alcohol hand rub (median log reduction on hands assessed as 4.3) the risk would be reduced to an estimated 0.00005 infections per year, equating to 99.9996% median risk reduction compared with handwashing. 35 Table 6 – Risk of infection from handling raw beef contaminated with E. coli O157, and subsequent hand-to-mouth contact following handwashing or use of an alcohol handrub Log reduction on hands Mean Median Standard deviation Handwashing Median 0.3 (range 0.2 to 3.0) 1.25 x 10-2 1.18 x 10-10 7.52 x 10-2 Use of alcohol hand rub Median 4.3 (range 2.6-5.8) 1.15 x 10-2 3.71 x 10-13 7.26 x 10-2 Overall the key to targeted hygiene as outlined in this section is that it recognises that good hygiene is not a 'once weekly deep down clean': it needs to be an ongoing part of our daily lives such that appropriate hygiene measures are targeted where and when necessary to halt the spread on infection. The need for effective hygiene processes is discussed in more detail below. 4. ESTABLISHING THE LINK BETWEEN TARGETED HYGIENE AND HEALTH BENEFITS Data showing the strong association between hygiene and the prevention of infectious diseases come from a range of sources including epidemiological and microbiolgical/biological plausibility data.2,14,24,128,129 Across Europe, the targeted approach to hygiene is now being accepted as the optimum means for developing an effective code of hygiene practice for the home. The approach is well supported by the growing database of microbiological evidence directly relevant to the home. This evidence is reviewed in a number of IFH and other reports.2,24,129,130 The validity of a risk-based approach is well established through several decades of application in food, pharmaceutical and cosmetics industries. It is also now being used to develop strategies for reducing healthcare–associated infections. A risk-based approach, for example has been adopted in developing the WHO Global Patient Safety Challenge to promote hand hygiene in healthcare facilities; the central concept ‘My five moments for hand hygiene’ focuses, not just on getting people to wash their hands, but to do it at the right time and in conjunction with other critical control measures.104 In contrast to the large database of microbiological data to support a risk-based approach, however, there are few or no intervention study data that directly assess the impact of targeted hygiene on infection rates in the home. This means that there is no quantitative data that can be used to assess the relative benefits of investment in targeted hygiene promotion compared to other interventions such as vaccination programmes. The exception to this is two specific interventions which are an integral part of targeted hygiene, namely hand hygiene and point- of-use water treatment in the home. Currently, there is a tendency to demand that data from intervention studies should take precedence over data from other sources in formulating public health policy. Although there are those who still adhere to this, it is increasingly accepted that, since transmission of pathogens is highly complex, involving many different pathogens each with multiple routes of spread, infection control policies and guidelines must be based on the totality of the evidence including experimental microbiological and other data. This is particularly important for home hygiene, for which little or no intervention data are available and where it is virtually impossible to 36 isolate the effects of specific hygiene procedures (hand washing, surface hygiene, laundry, washing and bathing etc). In optimising the targeted approach to hygiene, one thing that is needed is an accepted system for establishing the effectiveness of hygiene processes under use conditions and comparing the effectiveness of processes that involve “germ removal” with those that involve “germ kill”. Although suspension and surface tests, such as those developed by CEN and Association of Official Agricultural Chemists (AOAC), are important for establishing and comparing efficacy of disinfectant products under standardised conditions, manufacturers need to develop “in use” models, such as those described in the examples outlined above, to better ensure that products and processes (which may involve combinations of germ removal with germ kill) deliver effective hygiene under use conditions, and in consumers’ hands. The production of standardised Phase 3 or “in use” tests by standards bodies such as CEN is not a realistic option since the range of applications for biocidal products is infinite. What is needed is official guidelines and criteria (repeatability and reproducibility, adequacy of controls, peer review etc) that can be used by manufacturers and regulatory authorities to judge the validity of models used to evaluate the efficacy of hygienic cleaning processes under use conditions. This principle is outlined in the CEN standard “Chemical disinfectants and antiseptics – Application of European Standards for Chemical Disinfectants and Antiseptics.”131 5. IFH – DEVELOPING AND PROMOTING THE TARGETED APPROACH TO HOME HYGIENE As part of our work in promoting hygiene, the IFH has produced a set of 'Guidelines for Home Hygiene' together with 'Recommendations for selection of suitable hygiene procedures'.132,133 These are based on the risk-based approach, and cover all aspects of home hygiene including food and water hygiene, hand hygiene, general hygiene, personal hygiene, care of pets, care of risk groups etc. IFH, in collaboration with the UK Infection Prevention Society, has also produced a teaching resource which presents home hygiene theory and practice in simple practical language which can be understood by community workers with relatively little infection control background. 112 Most recently IFH has produced a range of plain language fact/advice sheets on home hygiene and hygiene issues. All of these materials are available through the IFH website (www.ifh-homehygiene.org) and are being promoted through a range of activities (conferences, exhibition stands, partnership with other organisations etc). If programmes to promote hygiene are to be successful in achieving behaviour change, there are however a number of challenges. Experience now shows that strategies that aim to change health behaviour simply by educating the public about the risks of infection and instructing them about hygiene have little success. We need to develop strategies based on understanding people’s motivations for hygiene behaviour. In recent years, hygiene has had a somewhat negative image and has come to be seen as old-fashioned and disciplinarian. We need to make hygiene more appealing to the public by realigning it with positive attributes of health and wellbeing. Equally we must recognise the people are entitled to freedom of choice according to their personal assessment of their needs, priorities and values. Persuading the public of the need to share responsibility without being accused of shifting blame may however be a significant challenge. In recent years, a significant amount of research has been done to identify strategies for changing hygiene behavior. Whilst we recognise that this aspect is fundamental, it is outside the scope of this report and is reviewed elsewhere.134, 135,136,137 37 6. SUSTAINABLE HYGIENE – THE KEY FACTORS As outlined in the introduction to this report, hygiene has the potential directly to improve sustainability because its aim is to promote and protect health. Good health is fundamental to the concept of a sustainable future and poor health is a severe and increasing burden on economic sustainability. The hygiene measures used, however, must themselves be sustainable. Most aspects of the sustainability of hygiene measures, notably those that involve environmental impacts or safety, are typical of those arising in product and process life cycles generally. Two specific possible longterm impacts, however, need additional consideration. First, there is the question of whether protection against infection by limiting microbial exposure might in some circumstances also have some adverse consequences i.e. the sustainability of hygiene per se. Second is the question of whether use of biocides to deliver hygiene might have additional impacts. Sustainability and sustainable development are concepts that refer to meeting the needs of society, and improving quality of life, in a way that does not jeopardise the ability of future generations to meet theirs. Many aspects of modern life are currently unsustainable, in that they are consuming resources or having other impacts (e.g. on climate change) at a rate that cannot be sustained indefinitely. Equally, the world is ever changing, and sustainability is not an absolute condition which can be attained and be expected to remain attained; sustainability is an ongoing goal to be pursued through continual improvement. A key tool used in sustainability assessment is Life Cycle Assessment (LCA). This methodology evaluates, in a quantitative way, the significant environmental impacts of products or processes in terms of inputs required (such as materials, energy, water) and outputs (such as emissions and waste). It is eminently applicable to evaluating sustainability of hygiene products (such as soaps, cleaners, disinfectants, paper towels) and procedures (such as washing in hot water or heat sterilisation). However, while LCA can ascribe numerical values with some degree of accuracy to individual impacts from a particular process, the relative importance of different types of impact is subjective and variable according to prevailing conditions and even value judgements. In most cases, assessments are concerned with comparing options, rather than ascribing exact values. Improvements are more likely to be achieved by seeking improvements in sustainability profiles (e.g., where some impacts can be improved markedly, others stay the same) rather than trying to declare one of two options with disparate impacts to be the more sustainable. Numerous tools and initiatives are being developed to improve sustainability: it is not the purpose of this document to review and assess these, which is outside the expertise of IFH, simply to highlight important considerations when these tools are applied to hygiene and prevention of infection. In the case of hygiene, sustainability assessments need to systematically compare alternative ways of delivering the same end result. It is thus important that desired results are defined, not only in terms of e.g. acceptable contamination levels but also in terms of the reliability or likelihood with which they can be achieved. Assessments must in principle consider the whole process and impacts throughout the life cycle, but of course interchangeable elements within a process (e.g. alternative products or procedures) can be compared provided this is done on the basis of the same end result. A sine qua non as regards sustainability is assurance of safety for people and the environment. This can generally be assessed for formulated hygiene products using 38 well-established chemical risk assessment techniques, and manufacturers have clear responsibilities to ensure the safety of their products. A substantial number of ingredients commonly used in formulated hygiene products already have detailed, published, risk assessments, e.g. under the EU Existing Chemicals legislation, OECD (Organisation for Economic Development and Co-operation) programmes and through voluntary industry initiatives such as HERA (Humanities in the European Research Area). Such risk assessments are now a formal requirement under the REACH legislation. These risk assessments and associated legislation consider in detail the hazards of substances used as ingredients and assess for each significant use scenario, including hygiene, whether exposure may be sufficient to give rise to any significant risk. Where necessary, appropriate controls (risk management measures) are then applied to ensure there will be no appreciable risk in use. Taking the above as background, the two additional questions that relate specifically to hygiene to can now be considered: 1. Sustainability of hygiene as an infection prevention measure In delivering infectious disease prevention through hygiene, the sustainability of hygiene itself must be considered. On one hand it must be designed to optimise protection against exposure to harmful microorganisms, but the possibility that reduced contact with such organisms could have some adverse effect also needs to be considered. The prime example of such a potential effect is known as the ‘hygiene hypothesis’. This hypothesis was first formulated in 1989 by Strachan who observed that there was an inverse relationship between family size and development of atopic disorders – the more children in a family, the less likely they were to develop these allergies. From this, he hypothesised that lack of exposure to “infections” in early childhood, transmitted by contact with older siblings could be a cause of the rapid rise in atopic disorders over the last thirty to forty years. Strachan further proposed that the reason why this exposure no longer occurs is, not only because of the trend towards smaller families, but also “improved household amenities and higher standards of personal cleanliness”. Although there is substantial evidence that some microbial exposures in early childhood can in some way protect against allergies, there is no evidence that we need exposure to harmful microbes or that we need to suffer a clinical infection.138,139,140 Nor is there evidence that hygiene measures such as handwashing, food hygiene etc. are linked to increased susceptibility to atopic disease.138,139 If this is the case, there is no conflict between the goals of preventing infection and minimising allergies. A consensus is now developing among experts that the answer lies in more fundamental changes in lifestyle that have led to decreased exposure to certain microbial or other species, such as helminths, that are important for development of immuno-regulatory mechanisms.141 There is still much uncertainty as to which lifestyle factors are involved. There is also no evidence to suggest, as is often stated in the media, that we need to get regular infections to boost our general immunity to infection. Weighed against any possible beneficial effects, there is now growing evidence that respiratory viruses are a risk factor for asthma and may actually exacerbate attacks.142,143,144 Alarmist media coverage of the hygiene hypothesis has declined, and become more representative of expert consensus. But a strong ‘collective mindset’ has become established that dirt is ‘healthy’ and hygiene somehow ‘unnatural’. This has caused concern among health professionals that the hygiene behaviours of the general public, which are the foundation of public health and our protection against infectious 39 disease, may become undermined.145 The reality is that, without clear evidence of the need for exposure to infectious doses of pathogens (or suffering an infection) to develop a healthy immune system, set against the firm knowledge that germ exposure can cause disease, encouraging lower standards of hygiene in order to reduce the burden of allergic diseases would be a reckless and ill-advised strategy with potential major adverse consequences for public health. We are only now beginning to understand how the normal resident and environmental flora interact within the body to maintain a healthy immune system. It is thus a prudent and precautionary approach that hygiene measures should be targeted where they are most needed so as to avoid unnecessary disruption of natural flora of both the human body as well as the environment. We need to explain the difference between ‘dirt and ‘germs’ and promote a more balanced understanding of the issues. This will enable people to see how they can follow a healthy lifestyle that involves “getting dirty” while still maintaining hygienic behaviours that seek to minimise risks of exposure to germs. 2. Sustainability of the use of biocidal products and other biocidal processes An implicit part of the IFH targeted hygiene approach, as outlined in this report, is that, if we are to deliver hygiene at the critical points as needed to break the chain of infection transmission, biocidal products and processes are required in certain situations. The sustainable use of biocides and biocidal products in terms of life-cycle impacts, and their human and environmental safety can be assessed and assured, as described above. The Biocidal Products Directive, now requires full human health and environmental risk assessments to be prepared in the coming years for all other biocides in relation to their uses and indeed individual biocidal products will also require authorisation under BPD. Those not giving satisfactory risk assessments will be restricted or removed from the market. In assessing these issues, we need to bear in mind however that biocides are not a fundamentally distinct group of compounds. While some biocides have been developed and are exclusively used for their biocidal activity (e.g. triclosan, phenolics, chlorhexidine, preservatives), there are many other substances that are used in cleaning products (e.g. soaps, detergents, acids etc) which are not traditionally regarded as biocides, but which can also have significant biocidal action. Some compounds (e.g. hydrogen peroxide, hypochlorites, common acids) are multifunctional i.e. they are included in products with the intention of providing both a cleaning as well as a biocidal action. There are also families of substances (e.g. quaternary ammonium compounds, alcohols, aldehydes) normally regarded as biocides in which some members have little or no activity. Thus in most respects the sustainability of biocides and biocidal products (in terms of life-cycle impacts), and their human and environmental safety, can be assessed and assured in just the same way as other ingredients and products. They will have a wide range of human and environmental safety profiles, but, from existing knowledge of chemical hazards, it is apparent that these are not uniformly more adverse than other ingredients. Currently, detailed human and environmental risk assessments are published for relatively limited range of biocidal ingredients, though human safety assessments for biocidal ingredients used in cosmetics and personal care products are also available. Once the safety of a biocidal product is assured as above, i.e. no significant risk of adverse effects, it could be argued that ingredients could then be selected only in 40 relation to their relative life-cycle impact profiles. On the other hand, from a sustainability viewpoint, it makes sense that ingredients with more favourable environmental and human safety profiles should be preferred, all other things being equal, as this could usefully increase margins of safety and provide added assurance for the future against any hitherto unsuspected effects. Favourable environmental safety characteristics for example include ready degradation or removal during sewage treatment, and low lipophilicity and thus a low potential to bioaccumulate. In general terms, ingredients whose hazards are well understood and characterised might likewise be preferred to those where there is greater uncertainty. Apart from the above considerations of life-cycle impacts and safety, one question that has particular relevance is whether use of biocidal products might encourage the emergence or proliferation of so-called 'superbugs' which are resistant to antibiotics. There is also concern that widespread use of biocides may lead to resistance to those biocides. From a literature review in 2002146 (updated in 2004147), IFH has concluded that, although laboratory experiments demonstrate links between exposure to certain biocides and increased resistance to antibiotics, there is currently no evidence that use of biocides in the community is linked to emergence and spread of antibiotic resistance; antibiotic misuse is the most significant causative factor. These conclusions differ only in emphasis from those expressed in a 2009 report from the EU Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR)148 which concluded that current scientific evidence does indicate that use of certain types of active substances in biocidal products in various settings may contribute to increased occurrence of antibiotic resistant bacteria. They further conclude that, to date, the lack of precise data, in particular on quantities of biocides used, makes it impossible to determine which biocides create the highest risk. Their conclusions are that “the most studied biocides, triclosan and quaternary ammonium compounds, are likely to contribute to maintaining selective pressure allowing the presence of mobile genetic elements harbouring specific genes involved in the resistance to biocides and antibiotics. However, the lack of data on the other biocidal compounds prevents reaching a definitive answer as to their role in selecting for or maintaining bacterial antibiotic resistance”. Overall however both the IFH and SCENIHR reports stress the important role of biocides in the control of microbes in a variety of applications. Both reports caution that biocides are a precious resource that must be managed through appropriate and prudent use. IFH further concludes, as have others 50 that, as antibiotic resistance continues to reduce our ability to treat infections, infection prevention through good hygiene in hospitals and in the community becomes of even greater importance. By reducing the number of infections through effective hygiene, the number of courses of antibiotic treatment prescribed can also be reduced, which can in turn reduce the impact of antibiotic resistance. IFH recommends that, wherever possible, biocides should be used at concentrations and under conditions that give rapid and effective inactivation of microbes. Reactive biocides (e.g. peroxide and hypochlorite bleach) and those which evaporate (alcohols) or disappear rapidly, leaving bacteria with no residue to which to develop tolerance, should be preferred. IFH has also addressed the concern that widespread use of biocides may lead to resistance to those biocides. After review146,147 IFH has concluded that although laboratory studies provide evidence that prolonged exposure to low levels of certain 41 biocides can be associated with reduced microbial susceptibility to those biocides, there is currently no evidence that biocide usage at its current levels (i.e. in the domestic and other settings) compromises effectiveness of hygiene procedures under in-use conditions. Again, however, prudent use is advised. 7. TARGETED HYGIENE – A FRAMEWORK FOR SUSTAINABLE HYGIENE IN THE HOME AND EVERYDAY LIFE In this review the targeted or risk-based approach to home hygiene, as developed by the IFH, is outlined. The aim of this approach is to maximise protection against exposure to infectious agents by breaking the chain of infection transmission. The essence of targeted hygiene is that it works to ensure, as far as possible, that hygiene interventions are focussed on situations where they maximise protection against infection, rather than in situations where there is little risk. Whilst targeted hygiene was originally adopted by IFH as a means to develop an effective code of hygiene practice for the home, it also provides a framework for sustainable hygiene because, through prudent and focussed use of hygiene products and processes, it: minimises the life-cycle impacts of hygiene processes, and maximises safety margins against any hazards of their use minimises any risks of development of antibiotic resistance from exposure to low level biocide residues seeks, as far as possible, to sustain “normal” levels of exposure to the microbial flora of our environment to the extent that is important to build a balanced immune system. In developing and/or selecting biocidal products or processes for use within a targeted approach to hygiene, a number of issues need to be considered in order to satisfy the above criteria and thereby maximise sustainability: We need to select the most appropriate biocides. This means selecting, as far as possible: biocides that are effective against the spectrum of organisms that represent a risk in the particular situation in which it will be used biocides that have a rapid biocidal action in order to break the chain of infection transmission (e.g. on hands, hand contact and food contact surfaces) with minimum delay. Note: In some situations (e.g. controlling growth of potentially harmful fungal contamination on damp surfaces such as tiled walls) a sustained biostatic (growth inhibiting) action is appropriate biocides and biocidal products that are not environmentally persistent or bioaccumulative, for which potential adverse effects are well characterised and understood, and where there are good margins of safety. We need to think more innovatively about delivery of hygiene. For example, can we use our growing understanding of microbial attachment and detachment to better design products and processes that efficiently combine prevention of germ attachment, germ removal and control (germ kill) in order to deliver the necessary hygiene result in a more sustainable way? We need to ensure that, as far as possible, we use “doses” of biocidal products and processes (cleaning, biocidal and physical agents either singly alone or in combination) which achieve hygienic cleaning of sites, surfaces, fabrics etc with minimum use of water, power or chemicals. This in turn however depends on developing in use/field test models which most closely mimic conditions of use and allow comparison of processes that involve both germ removal and germ kill. We need to think more holistically about delivery of hygiene in relation to sustainability i.e. in developing and selecting the most suitable hygienic cleaning 42 method for any situation, we need to consider ALL factors (infectious disease prevention, environmental and human safety, sustainability, antimicrobial resistance, the immune system) rather than each factor in isolation. The key to targeted hygiene is the recognition that good hygiene requires well formulated products that can deliver “hygienic cleaning” through either germ removal or kill (or combinations of processes) in order to break the chain of infection transmission. Targeted hygiene will not be delivered by adding arbitrary amounts of biocides to cleaning products in order to give a “bit of extra hygiene”. 8. CONCLUSIONS AND RECOMMENDATIONS The evidence presented in section 2 of this report shows that infectious diseases circulating in the home and community are a continuing and significant burden on the health and prosperity of the EU, which could be significantly reduced by better standards of hygiene. In Europe, it is estimated that up to 86% of deaths are now attributed to chronic conditions. These mortality statistics have driven public health investment towards reducing death rates from non-communicable diseases. The chronic disease problem however masks the triumphs of the public health and medicine that rolled back communicable disease mortality during the 20th century. The quandary of public health lies in the fact that successful communicable disease control is indirectly responsible for high chronic disease mortality statistics and the shift of investment away from the very systems that maintain it. It is now apparent that there is need for more investment in controlling infection, not just in healthcare settings or in association with food hygiene, but across the community. There is also recognition that health service spending in Europe cannot be sustained at its current level, and there is thus need for more emphasis on disease prevention strategies. Vaccine and hygiene promotion strategies have the effect of reducing the burden of infectious disease and the need for investment in care of those who are infected. They can also reduce antibiotic prescribing which is driving the antibiotic resistance issue. In section 3 of this review the targeted or risk-based approach to home hygiene, as developed by the IFH, is outlined. The aim of this approach is to maximise protection against exposure to infectious agents by breaking the chain of infection transmission. This is achieved by the timely application of processes that eliminate or control microbial contamination at critical points in the chain of transmission. The evidence presented in section 3.2 indicates that if we are to deliver “hygiene” (i.e. a level of contamination not harmful to health) at the critical points, it requires use of biocidal hygiene products and processes (alone or in combination with germ removal) in certain situations. In developing and promoting hygiene practice in the home and everyday life, as discussed in sections 2 to 5, the issue of sustainability must also be addressed. As stated in section 7, whilst targeted hygiene was originally adopted by IFH as a means to develop an effective code of hygiene practice for the home, what it also does is provide a framework for building sustainability into hygiene because it minimises the life-cycle impacts of hygiene processes, maximises safety margins against any hazards of their use and minimises any risks of the development of antibiotic resistance from exposure to biocides. It also looks to sustain “normal” interaction with the microbial flora of our environment. In the last 20 years, we have seen growing investment across Europe in controlling infectious diseases, not only with the establishment of ECDC, but also through 43 national hygiene promotion programmes which recognise that if the burden of infectious disease is to be contained in a manner that is economically sustainable, it is a responsibility that must be shared by the public. In the UK, there has been an intensive interactive programme to improve standards of food hygiene in the home. In response to the need for education on respiratory hygiene, ECDC has produced an 'Influenza Communication Toolkit'149 for use by health communicators in devising campaigns to tackle seasonal influenza. In November 2007, the UK launched a winter communications campaign to encourage the public to practise correct respiratory and hand hygiene when coughing and sneezing.150 In recent months we have seen intensive investment in promotion of hand hygiene in the home and community as a means to mitigate the spread of swine flu. IFH believes, however, that the impact of hygiene promotion programmes on the public is being weakened by the fact that the different aspects of hygiene are being dealt with by separate agencies. This means that the information that the family receives is fragmented and largely rule-based. If things are to change we must recognise that fragmented, rule-based knowledge is not enough to meet the challenges we face. Hand hygiene, for example is a central component of all hygiene issues and it is only by adopting a holistic approach that the causal link between hands and infection transmission in the home can be properly addressed. At the very least we need to ensure that the principles of infectious disease transmission and the role of hygiene are part of the school curriculum. In line with this, the EU-funded eBug project is working to roll out education on antibiotic resistance and hygiene at primary and secondary school level across Europe.52 If we are to sustain a high level of protection for EU citizens against infectious disease, in the face of changing demographics and microbial evolution, and derive real health benefits from investment in hygiene promotion, IFH concludes that the various stakeholders need to work together to address the following issues: the public must be engaged so that they share the burden and bring the unique contribution that only they can make, through good hygiene in the home and community. To achieve this, hygiene promotion strategies should : be family-centred rather than agency-oriented, building on what people understand, know, and need to know. not only change behaviour but also engender more positive attitudes to hygiene as a means to achieve health, well being and prosperity. give people the opportunity for a more balanced understanding of how to protect themselves from infectious diseases in a world where they also have conflicting concerns about issues such as allergic diseases and the environment. the risk-based ‘targeted’ approach to home hygiene should be adopted as the basis for development of hygiene codes for the home and everyday life since it offers both the most effective approach to breaking the chain of infection transmission as well as an intrinsically more sustainable framework. within the targeted approach to home hygiene, we need not only cleaning products that facilitate germ removal, but also biocidal products and processes are required. These provide germ inactivation, alone or in combination with cleaning processes, which can be used to ensure the elimination of pathogenic contamination from critical control points when used by consumers. The selection of products or processes for hygiene tasks should be based on assessment of their sustainability and safety as well as reliability in delivering the required result. Additional potential impacts on bacterial resistance and immunity need to be considered and any risks need to be accurately weighed against the risks and impacts of infectious disease, and managed appropriately. 44 The European regulatory process should: Encourage and facilitate the development and marketing of products and processes that deliver hygiene in a safe and sustainable way, using combinations of germ removal and germ kill as appropriate. 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