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Hendra Virus and Nipah Virus
MANAGEMENT AND CONTROL
September 2000
Department of Health, Social Services & Public Safety
An Roinn Sláinte. Seirbhísí Sóisialta agus
Sábháilteacht Phoiblí
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Contents
FOREWORD
2
1.
BACKGROUND
Recognition of Hendra and Nipah viruses
Geographical distribution
Clinical features
Transmission
3
3
4
4
5
2.
ASSESSING THE RISK
Differential diagnosis
6
6
3.
MANAGEMENT OF A PATIENT INFECTED WITH HENDRA OR NIPAH VIRUS
Treatment and care
Protection of health care professionals
Laboratory diagnosis
Disinfection
Clinical waste
Post-mortem examination
Disposal of corpses
7
7
8
8
9
9
9
10
4.
PUBLIC HEALTH ACTIONS
Responsibility
Surveillance of contacts
Planning
Incident control team
Veterinary action where there is a suspect case of animal Hendra or Nipah virus in the UK
Media relations
Flowchart
11
11
11
12
12
14
14
15
APPENDICES
1.
Laboratory Containment Level 4
17
2.
High Security Infectious Disease Units and Laboratories
20
3.
Transportation of patients
21
4.
Isolation procedures and facilities
23
5.
The carriage of dangerous goods
26
6.
Laboratory investigations
29
7.
Clinical waste
31
8.
Health and safety law
33
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Foreword
This document has been prepared in light of the recent characterisation by the Advisory Committee on
Dangerous Pathogens of two Hazard Group 4 agents - Hendra virus and Nipah virus - that caused zoonotic
disease in horses (1994) and pigs (1998) respectively. As these animals are frequently traded or mix with animals
from other countries during international events, for example Olympic equestrian events, transmission of these
viruses is an increasing possibility, both to other animals and those who care for them.
The Department of Health, in conjunction with the Ministry of Agriculture, Fisheries and Food, the Public
Health Laboratory Service, the Health and Safety Executive and independent experts, has prepared these
guidelines. Both the Advisory Committee on Dangerous Pathogens and the National Zoonoses Group for
England have been consulted on the contents.
These guidelines are primarily intended to advise health care professionals who may be contacted during exposure
incidents. They will wish to take account of the actions described in Chapter 4 in particular.
The document is also being made available to others in the medical and allied professions and to anyone else with
an interest. It is being published on the Department of Health’s website at: www.doh.gov.uk/hendra_nipah/
Prof Liam Donaldson
Chief Medical Officer for England
Dr H Campbell
Chief Medical Officer for Northern Ireland
Sir David Carter
Chief Medical Officer for Scotland
Dr Ruth Hall
Chief Medical Officer for Wales
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1. Background
Recognition of Hendra and Nipah Viruses
1.
Both Hendra virus (formerly called equine morbillivirus) and Nipah virus are newly recognised zoonotic
viruses that have caused disease in animals and, via contact with infectious animals, in humans. The
viruses are named after the locations where they were first isolated, in Australia and Malaysia respectively.
2.
Both viruses are members of the Paramyxoviridae family, and are classified as Hazard Group 4 agents
on the Approved List (approved by the Health and Safety Commission) made under Section 15 of the
Health and Safety at Work etc. Act 1974. The Control of Substances Hazardous to Health (COSHH)
Regulations, 19991 impose particular requirements for the handling of biological agents on the
Approved List. These viruses have been brought together for the purposes of these guidelines. The
definition of a Hazard Group 4 agent is “a biological agent that causes severe human disease and is
a serious hazard to employees; it is likely to spread to the community and there is usually no effective
prophylaxis or treatment available”. Distinctions between the viruses, for example in the diseases that
they cause, have been made clear wherever possible within this guidance.
Hendra virus
3.
Human cases of Hendra virus infection have been associated with two outbreaks to date.2 Hendra virus
was first isolated from horses during an outbreak in Brisbane, Queensland, Australia, in September
1994. Of the 20 horses that suffered from severe respiratory disease, 13 died. Two people looking after
the index horse case developed the disease, and one of them died. In 1995, a third human case (also
fatal) was recorded, and thought to be associated with an earlier outbreak in another part of Queensland.
The patient had assisted in the post-mortem examinations of two horses in August 1994. These three
cases are the only known occurrences of Hendra virus infection in humans.
4.
The most recently reported animal case of Hendra disease was an isolated confirmed case of a horse
in Cairns, North Queensland, in January 1999, which later died.
Nipah virus
5.
1
2
3
Nipah virus was first isolated in 1999, during an outbreak of viral encephalitis in the Malaysian regions
of Perak, Negeri Sembilan and Selangor, between September 1998 and April 1999. The total number of
suspected human cases was 265, of which 105 were fatal.3 Those mainly affected were pig farmers, who
had had close contact with infected and sick pigs. The outbreak was initially thought to be Japanese
encephalitis, but was later confirmed as Nipah virus infection.
Control of Substances Hazardous to Health Regulations (1999). In Northern Ireland Control of Substances Hazardous to Health
(COSHH) Regulations (Northern Ireland) 2000 apply. General COSHH ACOP (Control of substances hazardous to health) and
Carcinogens ACOP (Control of carcinogenic substances) and Biological agents ACOP (Control of biological agents). HSE Books (ISBN
0717616703).
Mackenzie JS (1999). Emerging viral diseases: An Australian perspective. Emerging Infectious Diseases 5(1):1–8.
Chua KB, Bellini WJ, Rota PA et al. (2000). Nipah virus: A recently emergent deadly paramyxovirus. Science 288:1432 – 1435.
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Hendra Virus and Nipah Virus
6.
During March 1999, 11 abattoir workers in Singapore developed a febrile illness (1 fatality) caused
by Nipah virus, following close contact with pigs imported from Malaysia. No new cases have been
documented in Singapore since restrictions on pig importation were imposed.
Geographical Distribution
7.
The exact geographical distribution of both Hendra and Nipah viruses has not yet been defined,
although, on the basis of known incidents, Australia and South East Asia should be considered as
endemic areas. Fruit bats of the genus Pteropus, (also known as the “flying fox”), are the suspected
natural host of both Hendra and Nipah viruses.4 They are distributed across an area encompassing
North, East and South-East areas of Australia, Indonesia, Malaysia, the Philippines and some of the
Pacific Islands. Fruit bats infected with Hendra virus have also been reported in Papua New Guinea.
8.
There have been no suspected or confirmed cases of human infection with either Hendra virus or Nipah
virus in the United Kingdom to date. In January 1999, five horses imported from Australia were under
surveillance having been in contact with a suspected animal case of Hendra virus infection. Laboratory
investigations finally excluded Hendra virus infection from the differential diagnosis of the index case.
9.
On 26 July 1999 a decision was made by the European Commission (99/507/EC) to restrict the entry of cats
and dogs into the EU from Malaysia, and cats from Australia until shown to be negative for Hendra virus and
Nipah virus, and officially certified as such. This follows similar import restrictions for both bats and horses.
Clinical Features
10.
The incubation period for Hendra and Nipah virus infection is generally between 4 and 18 days,
although some reports suggest that the incubation period may, in exceptional circumstances, be
up to twelve months (as evidenced by the events described in paragraph 3).
11.
Of the human cases reported to date, clinical symptoms have ranged in severity from mild to fatal.
Onset of disease is usually influenza-like with high fever and myalgia. Sore throat, dizziness, drowsiness
and disorientation have also been described. The case fatality rate for clinical cases is about 50%, and
subclinical infections may be common.
Hendra virus
12.
In the first two human cases of Hendra virus infection described, the patients displayed respiratory
symptoms, and eventually respiratory failure due to pneumonitis, causing death in one. The other
recovered slowly over a 6 week period. In the third, mild meningoencephalitis progressed to severe
encephalitis with convulsions, and eventually led to a coma and death.
Nipah virus
13.
4
4
The symptoms of disease associated with Nipah virus in humans have been described as febrile
encephalitis and respiratory illness. Later stages of the disease may be accompanied by autonomic
instability with fluctuating blood pressure and body temperature.
Young PL, Halpin K, Selleck PW et al. (1996) Serological evidence for the presence in Pteropus bats of a paramyxovirus related to equine
morbillivirus. Emerging Infectious Diseases 2(3): 239–240.
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Background
Transmission
Reservoir host
14.
Fruit bats are thought to be the natural host of both Hendra and Nipah viruses. Infection is widespread
and asymptomatic in this animal. Despite frequent contact between fruit bats and humans, studies have
shown no serological evidence of infection in bat carers.5
Hendra virus
15.
Laboratory investigations have found that animals other than horses are susceptible to Hendra virus.
Horses, cats and guinea pigs all suffer severe disease, and can excrete the virus in their urine. Fruit bats
become infected but do not become ill.
Nipah virus
16.
The first cases of porcine Nipah virus infection occurred on a farm in which fruit trees, frequented by
fruit bats, were planted close to pigpens. During the outbreak, antibodies to the virus were detected in
other domestic and wild animals – dogs, horses, cats and goats. The role of these animals in the spread of
infection has not yet been determined.
Mode of transmission
17.
It is unlikely that either of these viruses are easily transmitted to man, although previous outbreak
reports suggest that Nipah virus is transmitted more readily than Hendra virus (see paragraph 5). The
risk of transmission from horse to human is thought to be very low.6 Human-to-human transmission
of both Hendra and Nipah viruses has not been reported. The mode of transmission from animal to
animal, and from animal to human is uncertain, but appears to require close contact with contaminated
tissue or body fluids from infected animals.
18.
Experimental studies with both viruses have confirmed the possibility of transmission via close contact with
infected body fluids (through cuts and abrasions). Aerosol transmission does not seem to be significant.7, 8
19.
It should be noted that animals may incubate the virus for up to 18 days and although asymptomatic,
are infectious during this period.
20.
Those in close contact with animals from endemic areas should wear appropriate personal protective
equipment (PPE), such as disposable impermeable gloves, disposable gowns and face visors (which
provide both face and eye protection).
5
6
7
8
Selvey L, Taylor R, Arklay A, and Gerrard J (1996). Screening of bat carers for antibodies to equine morbillivirus. Communicable
Diseases Intelligence 20: 477-478.
McCormack JG, Allworth AM, Selvey LA et al. (1999). Transmissibility from horses to humans of a novel paramyxovirus, equine
morbillivirus (EMV). Journal of Infection 38: 22–23.
Williamson MM, Hooper PT, Selleck PW et al. (1998). Transmission studies of Hendra virus (equine morbillivirus) in fruit bats, horses
and cats. Australian Veterinary Journal 76:813–818.
Middleton D, Westbury H, Morrissy C et al. (1999). Experimental transmission of Nipah virus infection to pigs and cats. In: Programme
and abstracts of the XII International Congress of Virology (Sydney, Australia). International Union of Microbiological Societies, 39.
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2. Assessing the Risk
21.
The risk of transmission of either Hendra or Nipah virus from sick animals to humans is thought to be
low. Because of the paucity of information, there is no means to identify those at low, medium or high
risk of infection. However, all those who come into either regular or occasional contact with sick horses
(for Hendra virus) or sick pigs (for Nipah virus), should be considered to be at risk of infection,
particularly if the animal has been in an area where the virus is known to be endemic, or in an area
inhabited by fruit bats.
22.
It is thought that humans at greatest risk of infection are those who have been in an endemic area within
the previous 28 days and who have had close contact with either a horse suspected of being infected with
Hendra virus, or a pig suspected of being infected with Nipah virus.
23.
A clinical case definition may include:
•
acute viral, flu-like illness;
•
neurological/respiratory involvement;
•
encephalitis/pneumonitis;
•
an incubation period of 4 to 18 days. As there may be a longer incubation period
(e.g. 12 months), suspected cases may not show clinical symptoms.
Differential Diagnosis
24.
If a patient has been in the North, East or South-East areas of Australia, Indonesia, Malaysia, the
Philippines, Papua New Guinea and some of the Pacific Islands during the past month, infection with
Hendra or Nipah virus should be included in the differential diagnosis. However, because of the limited
knowledge about this disease, it is important that other countries should not necessarily be excluded.
25.
Although initial presentation is usually with respiratory disease, it is possible that Hendra virus infection
may be confused with Herpes encephalitis or measles encephalitis.
26.
Initial confusion of Nipah virus with Japanese encephalitis virus was probably because Japanese
encephalitis virus is also associated with pigs, and is endemic in South East Asia including Malaysia.
Therefore, laboratory diagnosis may include investigations for Japanese encephalitis virus in addition
to Nipah virus.9,10
9
Goh KJ, Tan CT, Chew NK et al. (2000). Clinical features of Nipah virus encephalitis among pig farmers in Malaysia. New England
Journal of Medicine 342 (17): 1229–1235.
10 Lim CC, Sitoh YY, Hui F et al. (2000). Nipah viral encephalitis or Japanese encephalitis? MR findings in a new zoonotic disease. American
Journal of Neuroradiology, 21(3): 455–461.
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3. Management of a Patient Infected
by Hendra or Nipah Virus
Treatment and Care
27.
Treatment is generally a matter of providing intensive supportive care, although there is some evidence
that early treatment with an antiviral drug, such as ribavirin, can reduce both the duration of feverish
illness and the severity of disease. However, the effectiveness of this treatment is still uncertain.
Initial management of patients
28.
The risk of transmission of both Hendra virus and Nipah virus from sick animals to humans is thought
to be low, and transmission from person to person has not yet been documented. Therefore, the risk of
transmission of Hendra and Nipah viruses to health care workers is thought to be extremely low.
However, transmission is theoretically possible, as secretions contain the viruses. This is why they have
been categorised as Hazard Group 4 agents (see Appendix 1). For the purposes of these guidelines, the
risk is managed at Containment Level 4, bearing in mind that appropriate precautions need to be taken
in accordance with a local risk assessment. Those assessing the risk may find the Advisory Committee on
Dangerous Pathogens (ACDP) ‘Microbiological Risk Assessment: an interim report’11 helpful.
29.
Patients suspected of being infected by either Hendra or Nipah virus should be admitted (or transferred
if already in hospital) either to an intermediate isolation facility, or to a High Security Infectious Disease
Unit (HSIDU) (see Appendix 2), after consultation with the physician in charge. Such discussions are
particularly important if it is thought that movement will have a detrimental effect on the patient.
Discussions with specialist laboratories at the Central Public Health Laboratory (CPHL) and the Centre
for Applied Microbiology and Research (CAMR) (see Appendix 2) may also help with a decision
whether to move a patient whilst awaiting confirmation of laboratory diagnosis. Appendix 3 gives
guidance on the transportation of patients, and Appendix 4 describes isolation facilities.
30.
In the context of caring for a suspected or confirmed case of infection with Hendra or Nipah virus,
it is recommended that close contact with body fluids and infected tissues is avoided.
Transportation of patients
31.
Health authorities are responsible for securing suitable arrangements for the transportation of patients
known to be or suspected of being infected with Hendra or Nipah virus. Local policies should include
details of such arrangements. There are at present two HSIDUs in England, in London and Newcastleupon-Tyne (see Appendix 2). Patients should be transported at Ambulance Category 3, which signifies
that special precautions are required. Qualified ambulance personnel should use appropriate PPE
including disposable gloves, face and eye protection, as well as a disposable impermeable gown/apron.
More information on the transportation of patients can be found in Appendix 3.
11 Advisory Committee on Dangerous Pathogens (1996). Microbiological Risk Assessment: an interim report. HMSO (ISBN 0113219903.)
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Hendra Virus and Nipah Virus
Protection of Health Care Professionals
32.
Hendra virus and Nipah virus are biological agents to which requirements of the Control of Substances
Hazardous to Health (COSHH) Regulations 1999 apply.12 Both are classified as Hazard Group 4
biological agents.13 The COSHH Regulations require assessments to be made of the risks to health from
work activities, and prevention of exposure to risks, or adequate control measures to be put in place if
prevention is not possible. All health care workers should be provided with sufficient information,
instruction and training about the risks of exposure, and the precautions to be taken if they are likely
to be exposed to Hendra or Nipah virus.
33.
The number of persons attending a patient should be kept to a minimum. Nursing and medical staff
should be informed of the potential risks (see paragraph 32) particularly during periods of intensive care.
Suitable PPE, including disposable impermeable gloves, disposable gowns and face visors (which provide
both face and eye protection) should be used.
Laboratory Diagnosis
34.
Diagnosis should be undertaken as quickly as possible. Specimens from suspected Hendra or Nipah virus
infected cases should be sent to a High Security Infectious Disease (HSID) reference laboratory, either
CPHL or CAMR (see Appendix 2 for contact details).
35.
Tests for diagnosis include enzyme-linked immunosorbant assay, immunofluorescence, polymerase chain
reaction, virus neutralisation assays and tissue culture. Although none of the above assays is currently
available in the UK, the designated specialist laboratories are sufficiently experienced to undertake
preliminary virus isolation studies and a PCR system of identification with confirmation by experts
in Australia, Malaysia and at The Centres for Disease Control and Prevention (CDC), Atlanta, USA.
36.
All work involving the propagation of Hendra virus or Nipah virus must be done in Containment Level
4 facilities. Details on the requirements of Containment Level 4 can be found in Appendix 1.
37.
Once the diagnosis has been confirmed, all specimens should be correctly labelled, packed and stored.
Their handling should be tracked and audited.
38.
The local laboratory should discuss with the HSID reference laboratory whether to send or dispose
of any isolates or specimens taken before confirmation of the diagnosis or transportation of the patient
to an HSIDU. Any equipment involved should be disinfected or autoclaved as appropriate. Each case
should be discussed with staff in the laboratory first, so that specimens are transported correctly (UN
602 compliant packaging).
39.
Transport of Hendra virus or Nipah virus, other than in material for diagnostic purposes only, requires prior
notification to the Health and Safety Executive (HSE). COSHH Regulations 1999, The Carriage of Dangerous
Goods (Classification, Packaging and Labelling) and the Use of Transportable Pressure Receptacles Regulations
199614 apply to Hazard Group 4 agents. Specimens cannot be sent by post due to Post Office conditions of
carriage. Further details on the carriage of dangerous goods can be found in Appendix 5.
12 Control of Substances Hazardous to Health Regulations (1999). SI 1999/437. Stationery Office. In Northern Ireland Control of
Substances Hazardous to Health (COSHH) Regulations (Northern Ireland) 2000 apply. General COSHH ACOP (Control of substances
hazardous to health) and Carcinogens ACOP (Control of carcinogenic substances) and Biological agents ACOP (Control of biological agents).
HSE Books (ISBN 0717616703).
13 Advisory Committee on Dangerous Pathogens (1995). Categorisation of biological agents according to hazard and categories of
containment. Fourth edition. HSE Books (ISBN 0717610381).
14 In Northern Ireland the Carriage of Dangerous Goods (Classification, Packaging and Labelling) and the Use of Transportable Pressure
Receptacles Regulations (Northern Ireland) 1997 apply.
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Management of a Patient Infected by Hendra or Nipah Virus
40.
In exceptional circumstances, to preserve the life of a patient, general hospitals without immediate
access to a HSID laboratory may be obliged to conduct emergency tests to manage critically ill, high risk
patients. In such circumstances, advice should be sought from HSID specialists at an early stage, to agree
on what emergency tests may be undertaken (none of which should involve or allow replication of the
virus). Risks to hospital and laboratory staff must be minimised. This is strictly an emergency
arrangement and is not intended for continuing patient management, as specimen taking and handling
are the activities which could most likely lead to mishap and cross-infection. Further details on
laboratory investigation can be found in Appendix 6.
Disinfection
41.
Hendra and Nipah viruses are not known to be particularly resistant to heat or chemicals. Areas and
equipment which have not obviously been contaminated with blood, body fluids or laboratory
specimens, can be adequately treated by routine washing and cleaning methods.
42.
Objects that are soiled by infective or potentially infective secretions or excretions may be disinfected
by autoclaving or boiling. Where heat cannot be used, detergents or chemical disinfectants may be used.
Normal disinfection procedures can be applied for spillages of potentially infective material.
Disinfectants containing 10,000 ppm of available chlorine are recommended for spillages. The use
of sodium dichloroisocyanurate (NaDCC) granules is also generally recommended for clinical waste
spillages, because made-up solutions lose activity with time and require regular replacement.15
43.
Extreme methods of decontamination, such as the use of powerful chemicals or fumigation, are not
recommended.
44.
Spilled waste, and any absorbent material used to mop up waste, must be placed in a clinical waste
container for disposal as outlined in Appendix 7.
Clinical Waste
45.
Procedures for the safe disposal of specimens and decontamination of any equipment used, or areas
potentially contaminated, must be in accordance with the Schedule 3 of COSHH16 (see Appendix 7).
Post-Mortem Examination
46.
Under the hierarchy of controls required by COSHH, exposure to biological agents should be prevented
where reasonably practicable. A post-mortem examination on a person suspected or known to have died
from Hendra or Nipah virus exposes staff to unwarranted risk and should not be performed.
47.
Suspected cases would be those patients who have died from acute respiratory disease or acute
encephalitis where an alternative definitive diagnosis has not been made. If the diagnosis is in doubt,
a HSIDU (see Appendix 2 for contact details) can be contacted for advice.
48.
Needle necroscopy tests should also be discouraged. If thought essential, arrangements can be made for
experts to perform tissue sampling.
15 Public Health Laboratory Service (1993). Chemical disinfection in hospitals. HSMO (ISBN 0901144347).
16 Control of Substances Hazardous to Health Regulations (1999). In Northern Ireland Control of Substances Hazardous to Health
(COSHH) Regulations (Northern Ireland) 2000 apply. General COSHH ACOP (Control of substances hazardous to health) and
Carcinogens ACOP (Control of carcinogenic substances) and Biological agents ACOP (Control of biological agents). HSE Books (ISBN
0717616703).
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Hendra Virus and Nipah Virus
Disposal of Corpses
49.
10
Training and adherence to agreed protocols for safe procedures for body disposal are essential. Standard
procedures for burial or cremation apply, although the bodies of patients known or suspected to be
infected with Hendra virus or Nipah virus should not be embalmed. Embalming carries significant risk
to the operator, as sharp instruments need to be used and a substantial amount of blood is drawn.
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4. Public Health Actions
50.
Those thought to be at greatest risk of infection are those who have been in an endemic area within the
previous 28 days and who have had close contact with either a horse suspected of being infected with
Hendra virus, or a pig suspected of being infected with Nipah virus. See case definition at paragraph 23.
Responsibility
51.
Consultants in Communicable Disease Control (CCDCs), and Consultants in Public Health Medicine
for Communicable Disease and Environmental Health (CPHM (CD & EH)) in Scotland, are
responsible for leading the local public health response to known or strongly suspected human cases
of Hendra or Nipah virus infection. The State Veterinary Service (SVS)17 will deal with known
or suspected animal cases of Hendra or Nipah virus infection. There will be close liaison between
the CCDC/CPHM (CD & EH) and the SVS17 at all times.
Surveillance of Contacts
52.
If a horse is suspected of being infected with Hendra virus, or a pig suspected of being infected with
Nipah virus, possible human contacts should be traced and informed. The incubation period for Hendra
virus infection in a horse is 8 – 10 days. Horses with ‘transit fever’ may be mistaken for Hendra virus
cases, although ‘transit fever’ responds to antibiotic therapy within 24 – 48 hours. If there is no response
to therapy, an animal should be treated as a suspected case of Hendra virus infection.
53.
Hendra virus is a notifiable disease under the Specified Animal Pathogens Order 1998. Any person who
suspects or knows that an animal or carcass is infected with viable Hendra virus must report that fact
to a veterinary inspector. Nipah virus is not a notifiable disease.
54.
Hendra virus and Nipah virus infections in humans are not notifiable diseases under the Public Health
(Infectious Diseases) Regulations 1988. Nonetheless, it is advisable that CCDCs assume the
responsibility to ensure that all possible human cases are identified, and that surveillance is undertaken.
In Scotland, the CPHM (CD & EH) should inform the Scottish Centre for Infection and
Environmental Health (SCIEH) and the Scottish Executive of the identification of a probable or
confirmed case. The Director of Public Health (DPH) or Divisional Veterinary Manager (DVM) should
approach the CCDC / CPHM (CD & EH) who should keep a register of possible contacts. Those
individuals should be approached, interviewed, be given reassuring advice and provided with a basic
advice sheet. It is important to tell suspected cases that the likelihood of transmission is low, and that
person-to-person transmission has not been recorded for either Hendra or Nipah virus. Where possible
General Practitioner’s (GP) should be informed by the CCDC in writing with a fact-sheet so that they
are aware of the symptoms of this infection.
17 In Northern Ireland the Department of Agriculture and Rural Development (DARD) Veterinary Service.
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Hendra Virus and Nipah Virus
55.
Contacts of a suspected human case should be advised to visit their GP if they develop relevant
symptoms (feverish illness) in the following 3-6 weeks. They should inform their GP that they are under
clinical surveillance for either Hendra virus or Nipah virus infection, and take any relevant background
information and fact-sheets with them to their GP.
56.
Potential cases should be monitored for 2-3 weeks from the last possible date of exposure to infection,
and enquires made about the presence of any suspicious symptoms.
57.
If a person wishes to go abroad during a period of surveillance, the Public Health Laboratory Service,
Communicable Disease Surveillance Centre (CDSC) should be consulted before advice is given.
Planning
58.
CCDCs and local authorities should work together to prepare joint contingency plans for the control
of infectious diseases such as Hendra and Nipah virus, and work out details of local liaison with those
concerned. This should include involvement of local veterinary services.
59.
Although Hendra and Nipah virus infections are not notifiable diseases (see paragraph 54), all local
doctors should be advised to inform their local CCDC immediately, by telephone, if one of their
patients is suspected to be suffering from Hendra or Nipah virus infection.
Incident Control Team
60.
61.
12
When to form a team
The CCDC should convene an Incident Control Team (ICT) when there is a suspected or confirmed
case of human infection with Hendra or Nipah virus. The SVS will co-ordinate the veterinary aspects
of control centrally, liaising closely with the ICT and providing veterinary representation. In Northern
Ireland the DARD Veterinary Service will co-ordinate the veterinary aspects of control.
Who to include on the team
The ICT should seek support from the Regional Epidemiologist and CDSC in England and Wales,
the SCIEH in Scotland and the Regional Epidemiologist, CDSC (NI) in Northern Ireland. The team
should include expert representatives from veterinary and human health agencies. Where occupational
transmission is suspected, the Health and Safety Executive and the Local Authority Environmental
Health Officer should be informed (see Figure 1). When there is a suspected or confirmed case of
Hendra or Nipah virus in an animal in Great Britain, the SVS should be represented on the ICT.
In Northern Ireland the DARD Veterinary Service should be represented on the ICT. If infection
occurred abroad, there should be liaison with the authorities in that country.
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Management of a Patient Infected by Hendra or Nipah Virus
Actions for the incident control team
62.
The ICT, led by the CCDC, should implement an action plan as follows, adapted in accordance
with local needs.
Incident Control Team Action Plan (to be adapted to local needs)
To provide appropriate care of the patient
•
Ensure that the patient is admitted to a High Security Infectious Disease Unit (HSIDU) or other appropriate
isolation facility.
•
Confirm that all categories of staff likely to have contact with the patient, their clinical specimens, or their
body fluids, have been advised about appropriate control measures, including protective clothing.
To protect contacts of human or animal cases
•
Assess the risk of infection to those who have been exposed to a suspected or confirmed case of human or
animal Hendra or Nipah virus infection, arranging clinical surveillance where appropriate.
•
Ensure, in co-operation with the laboratories concerned, that any specimens connected with the patient
from tests that may result in propagation of the viruses, and which are not held in a HSID laboratory, are
located and retrieved. These may have been sent out before the diagnosis of Hendra virus or Nipah virus
was suspected.
•
Consider post-exposure anti-viral treatment (ribavirin) for those at risk of infection with Hendra virus or
Nipah virus. However, it should be noted that the efficacy of ribavirin in such situations is yet to be
established.
•
When there is a suspected or confirmed human case of Hendra or Nipah virus infection, arrange for the
disinfection of articles contaminated by the patient in the domestic setting before they were admitted to
hospital.
To communicate with others
•
•
Liaise with appropriate local health and veterinary services.
•
•
•
Inform the Department of Health (DH) or relevant UK Health Department.
•
Co-ordinate a response to media and public enquiries.
Inform all general medical practitioners, medical directors of all Trusts and the Accident and Emergency
Departments in the district, for appropriate cascade according to local plans.
Inform the Regional Health Authority under the “Untoward Incident” or similar arrangements.
Liaise with CDSC, who will liaise with the DH in ensuring appropriate communications in the UK and
internationally.
When there is a suspected or confirmed animal case
•
Co-ordinate a response to media and public enquiries.
•
Ensure that the appropriate Divisional Veterinary Managers and the Ministry of Agriculture, Fisheries and
Food (MAFF) are informed of the circumstances of the case as a matter of urgency. In Northern Ireland the
appropriate Divisional Veterinary Officer (DVO) and DARD should be informed.
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Hendra Virus and Nipah Virus
Veterinary Action when there is a Suspect Case of
Animal Hendra or Nipah Virus in the UK
63.
The control of an outbreak of Hendra or Nipah virus involving animal cases and human contacts
requires the concerted efforts of animal and human health services working in close liaison. The CCDC
should ensure that the Divisional Veterinary Manager (MAFF contact) or in Northern Ireland, the
Divisional Veterinary Officer (DVO, DARD contact) has been informed.
Media Relations
64.
Enquiries from the media may be expected at an early stage when there is a suspected or confirmed case
of Hendra or Nipah virus infection. It is essential that there should be close co-operation between press
offices involved, to ensure accuracy and consistency in the information and advice provided.
65.
The ICT should include an experienced press officer. Local outbreak plans should identify (before the
event) a named individual to act as press officer, and ensure, as far as possible, that all public statements
are made by one person, preferably the CCDC or the press officer, speaking for the health authority, the
local authority and the hospital. All enquiries from the media should be referred to this person.
66.
Close liaison between the CCDC, press officer, regional health authority and the DH is important.
A draft of any local press release should be sent electronically to the DH for consideration before issue.
The DH will also liaise with the MAFF, Public Health Laboratory Service and CAMR press officers.
CPHMs in Scotland should follow the equivalent procedure.
67.
Statements should as far as possible be factual, confirming the number of suspected and/or confirmed
cases. It is most important to make strenuous efforts to preserve the anonymity of patients and their
families, contacts and neighbourhood. At the same time, everything should be done to allay the fears
of the general public, in particular by pointing out the unlikelihood of any spread in the community.
68.
Given the importance of such an occurrence, a full report should be written up by the ICT and
submitted to the relevant UK Health Department.
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Management of a Patient Infected by Hendra or Nipah Virus
Flow Chart
69.
Figure 1 outlines the steps to be taken by the CCDC in the event of a suspected or confirmed case
of Hendra or Nipah virus infection in an animal or human.
Figure 1: Local public health control of a Hendra or Nipah
virus incident
Clinician, vet or laboratory
informs CCDC of strongly
suspected or confirmed case of
human Hendra/Nipah virus or
animal Hendra/Nipah virus with
known or suspected human contact
Form Incident or Outbreak Control Team
• Inform LA/PHLS (CDSC, CPHL)/RE/DH/HSE
• Trace, investigate and provide anti-viral treatment
for appropriate contacts of the case
• Advise on safety of animal/health care professionals
• Ensure retrieval of laboratory specimens
• Disinfect home
• Liaise with press
Is the suspected source
an animal in the United Kingdom?
Yes
• Liaise with MAFF
• Assess safety of workers
• Discuss with
VRD CPHL/CAMR
• Discuss with local clinicians
No
• Liaise with CVO
• Trace animal overseas
• Inform DH/CDSC
for follow up and
animal tracing abroad
Please note that this chart reflects public health control in England. For the devolved administrations, equivalent
bodies should be notified where necessary
70.
Key to abbreviations used in Figure 1: CCDC – Consultant in Communicable Disease Control; CVO –
Chief Veterinary Officer; LA – local authority; PHLS – Public Health Laboratory Service; CDSC –
Communicable Disease Surveillance Centre; CPHL – Central Public Health Laboratory; RE – Regional
Epidemiologist; DH – Department of Health; HSE – Health and Safety Executive; MAFF – Ministry of
Agriculture, Fisheries and Food; VRD – Virus Reference Division; VLA – Veterinary Laboratories Agency.
15
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Laboratory Containment Level 4
APPENDIX 1
Laboratory Containment Level 4
(Extract from ‘Advisory Committee on Dangerous Pathogens (1995) Categorisation of biological agents
according to hazard and categories of containment.’ Fourth edition. HSE Books. (ISBN 0717610381))
Laboratory Containment Level 4 must be used for all work with biological agents in Hazard Group 4.1
A detailed code of practice should be prepared for the laboratory and a safety officer should be appointed
and be directly accountable to the person identified as responsible for the work. Personnel should be over
the age of 18 and must be provided with suitable and sufficient information, instruction and training on
working in the laboratory. The work should be closely supervised. A list must be kept of employees
engaged in work with biological agents in Hazard Group 4 indicating the type of work done and, where
known, the agent(s) to which they are exposed. This must include, as appropriate, a record of exposures
(for example resulting from accidents and incidents). In general, this list must be kept for at least ten
years but Schedule 3 in COSHH shows that for some infections an extended period of up to 40 years
may be necessary.
Specific requirements for Containment Level 4 laboratories
1
The laboratory must be separated from any other activities in the same building (see point 15 below).
2
The laboratory must be maintained at an air pressure negative to atmosphere (see point 23 below). Input
air must be HEPA-filtered (or equivalent) and extract air double HEPA filtered (or equivalent) (see point
24 below).
3
Access to the laboratory must be restricted to authorised personnel and a key procedure established
so that entry is restricted at all times. Entry must be through an airlock.
4
The laboratory must be sealable to permit disinfection (see point 31 below).
5
There must be specified disinfection procedures.
6
Efficient control measures must be taken against insect and rodent vectors.
7
The laboratory must be easy to clean. Bench surfaces, floors, walls, and ceilings must be impervious
to water and resistant to acids, alkalis, solvents and disinfectants.
8
There must be secure storage of biological agents.
9
There must be an observation window or alternative so that the occupants can be seen.
10
The laboratory must contain its own equipment.
11
Infected materials must be handled in a Class III safety cabinet (see point 27 below), isolator or other
suitable containment offering an equivalent level of protection.
12
There must an incinerator on site for the disposal of animal carcasses.
1
Some agents in this group may be pathogens of animals (see ACDP Categorisation, 1995, Appendix 20). Certain additional control
measures specified by Agriculture Departments may be necessary to prevent their release to the environment.
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Hendra Virus and Nipah Virus
13
14
Personal protective equipment, including protective clothing, must be:
(a)
stored in a well-defined place;
(b)
checked and cleaned at suitable intervals;
(c)
when discovered to be defective, repaired or replaced before further use.
Personal protective equipment which may be contaminated by biological agents must be:
(a)
removed on leaving the working area;
(b)
kept apart from uncontaminated clothing and equipment;
(c)
decontaminated and cleaned or, if necessary, destroyed.
15
The laboratory unit should be a separate building or form an isolated part of a building.
16
There should be adequate space (24m3) in the laboratory for each worker.
17
The ‘clean’ side of the airlock (see point 3 above) should be separated from the restricted (‘dirty’) side
by changing and showering facilities and preferably by interlocking doors. The outer door should
be labelled with a ‘work in progress’ sign.
18
At all times during work in the laboratory/laboratory suite or unit there should be a second competent
person present to assist in the case of emergency.
19
High performance respiratory protective equipment (two or more units) should be available in the ‘clean’
side of the laboratory unit for use in an emergency.
20
There should be a telephone or other means of outside communication in the laboratory/laboratory suite.
21
A complete change of clothing should be worn in the laboratory unit. After work is finished, clothing
should be removed in the ‘dirty’ side of the changing area and placed in a container for autoclaving.
A shower should be taken before leaving the laboratory.
22
All effluent, including that from the shower, should be rendered safe before discharge.
23
The room in which the cabinet system is sited must be maintained at an air pressure negative to
atmosphere. ‘Atmosphere’ in this context may be taken to mean the external air and/or other parts of the
laboratory suite or building depending on the circumstances. In effect, this means arranging engineering
controls such that a continuous inward airflow into the laboratory is to be maintained but this is
necessary generally only when work with biological agents is actually in progress. Provision should be
made for comfort factors, i.e. supply of fresh air, temperature control.
24
The usual practice is to ventilate the laboratory unit through independent ducting by a plenum and
a total-loss exhaust air system. The exhaust air from the laboratory and the cabinet/cabinet system
(see point 27 below) must pass through two HEPA filters (or equivalent) mounted in series before it
leaves the laboratory unit. Use of twin filters for incoming air is also recommended as an additional
safeguard against filter or filter-seal failure.
25
A negative pressure of at least 70 Pascals (7 mm of water) should be maintained in the laboratory and
a negative pressure of about 30 Pascals (3 mm of water) in the airlock. An alarm system should be fitted
to detect any unacceptable change in air pressure and manometers should be displayed which can be
read from both inside and outside the laboratory.
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Laboratory Containment Level 4
26
The supply and extract airflows should be interlocked to prevent positive pressurisation of the laboratory
in the event of a failure of extract fans.
27
In practice, a sophisticated cabinet system or ‘cabinet line’ rather than a single Class III cabinet is
generally used in order to provide the necessary space for working safely and having direct access to
equipment such as a refrigerator, incubator and autoclave all of which are generally built into the
structure. The system, therefore, amounts to a series of interconnected Class III safety cabinets with
control and indicator devices built in. The integrity of such a complex installation must be most
carefully and regularly monitored to ensure that there are no leaks and that the specification, and
airflows through the system, are at least equivalent to those specified in BSEN 12469: 2000.
28
There should be a programme of regular validation of the continuing safe operation of control systems
(for example, checks on airflows, filter integrity, sensors, indicators, interlocks) coupled with routine
servicing and maintenance of all safety equipment and plant. COSHH Regulation 9 in referring to
maintenance, examination and test of control measures and specifically to ‘local exhaust ventilation’
must be observed. This means for example, that HEPA filters and their fittings and seals must be
thoroughly examined and tested at intervals not exceeding 14 months. In practice, depending on the
frequency of use, these tests are commonly carried out at shorter intervals, for example, six monthly.
29
An emergency electricity supply should be provided to cut in automatically in the event of a power failure.
30
An additional ventilated airlock may be required for bringing in larger items of equipment that cannot
pass through the personnel airlock or the autoclave. Larger equipment to be removed from the
laboratory should not be passed through the airlock until the laboratory and the equipment in it has
been decontaminated by fumigation or other measures appropriate to the circumstances.
31
COSHH requires that the Containment Level 4 laboratory is to be sealable to permit disinfection.
While the definition of ‘disinfection’ may be widely interpreted, in practice, it may be necessary to
decontaminate by fumigating the accommodation when, for example, a major spillage has occurred or
when maintenance work is to be carried out.
32
A double ended autoclave with interlocking doors with entry in the laboratory and exit in a ‘clean’ area
should be provided. It is preferable that the autoclave is built into the cabinet system.
33
Eating, chewing, drinking, taking medication, smoking, storing food and the application of cosmetics
should be forbidden.
34
Mouth pipetting should be forbidden.
35
All infectious material must be stored in the laboratory unit and nowhere else.
36
All material should be made safe or safe to handle before removal from the laboratory. A double-ended
dunk tank filled with an effective disinfectant, or a safe alternative system, may be required for the
removal of materials that cannot be autoclaved. The methods chosen for the removal of infected
materials, including all waste for incineration, should be authorised by the safety officer and specified in
the local code of practice. If a dunk tank is used, it should be sealed during fumigation if the disinfectant
it contains is likely to react with the fumigant to form toxic compounds.
37
All accidents and incidents (spills and other forms of exposures to infective materials) should be
immediately reported to and recorded by the safety officer who should take the appropriate measures
specified in the local code of practice, which must include the requirements for informing employees in
accordance with Schedule 3 of the COSHH Regulations.
19
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Hendra Virus and Nipah Virus
APPENDIX 2
High Security Infectious Disease Units and
Laboratories
High Security Infectious Disease Units and Patient Management
Laboratories:
Coppetts Wood Hospital
Coppetts Road
Muswell Hill
London
N10 1JN
Tel: 020 8883 9792
Newcastle General Hospital
Westgate Road
Newcastle-Upon-Tyne
Tyne and Wear
NE4 6BE
Tel: 0191 273 8811
High Security Infectious Disease Viral Diagnostics Laboratories:
Public Health Laboratory Service
Virus Reference Division
Central Public Health Laboratory
Colindale Avenue
London
NW9 5HT
Tel: 020 8200 4400
Centre for Applied Microbiology and Research
(CAMR)
Porton Down
Salisbury
SP4 0JG
Tel: 01980 612 100
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Transportation of Patients
APPENDIX 3
Transportation of Patients
Ambulances
1.
During transportation of patients, good ambulance practices and personal hygiene are the best defence
against most infectious diseases. When these alone are not considered sufficient, specific instructions will
be given by the senior medical officer at the HSIDU to ensure protection. This will normally be in
accordance with the Ambulance Service Infectious Disease Procedure (Ambulance Category III) and the
associated guidance.
2.
Infectious diseases are classified by the Ambulance Service into three categories (I, II, III) according to
the action necessary to safeguard ambulance staff during the ambulance transport. Moderate and highrisk patients, such as those known or suspected to be infected with Hendra or Nipah virus would be
classified as Ambulance Category III.
3.
Staff transporting patients must be qualified ambulance personnel, who should be adequately trained
and practised in the procedure.
4.
Regular training exercises with adjacent services and the designated HSIDU are recommended.
General guidance for the transport of patients – at Ambulance Category III.
•
All Ambulance Category III removals will be taken to a HSIDU, or intermediate isolation
facility, after consultation with the physician in charge.
•
Ambulances need not be stripped down completely (resuscitation equipment, oxygen supply etc.
should remain).
•
A bag and mask should be used to resuscitate all patients with infectious disease. Under no
circumstances should direct oral resuscitation be carried out.
•
Chief Ambulance Officers should ensure that there are clear operational instructions in place,
and that all staff, including Control Officers, are aware of:
–
the possible routes of transmission of Hendra and Nipah virus;
–
the importance of taking advice from the designated HSIDU on the provision of, and
requirement for, personal protective clothing and, where necessary, patient isolators;
–
arrangements for the journey to the designated HSIDU or intermediate isolation facility;
–
arrangements for disinfection procedures for the ambulance, the crew’s clothing, etc.,
and subsequent personal surveillance procedures.
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Hendra Virus and Nipah Virus
5.
In the case of long-distance journeys, an escort vehicle should be provided, but for most instances this
will not be necessary. In the event of a vehicle breakdown, the crew should radio the ambulance control
unit for a towing vehicle to be despatched. Under no circumstances should members of the crew who
have been in contact with the patient leave the vehicle on route. The crew should proceed as directed
to the entrance to the HSIDU, and once the patient has been handed over await instructions regarding
disinfection and decontamination procedures.
Air transportation within the UK
6.
Whenever possible road transport should be used in preference to air transport. However, if unavoidable,
ambulant and continent patients can travel by air ambulance with trained crews. For those patients who
are not ambulant or continent, if the necessary facilities are available, an air transport isolator held by the
RAF may transport them. Air ambulance crews should adopt the same protective precautions as road
ambulance crews.
International arrangements
7.
It is generally accepted on public health grounds, that persons suffering from Hendra/Nipah virus
infection should be treated locally rather than transported to areas where the diseases do not exist.
Nevertheless, instances may arise where it becomes necessary to transport a confirmed or suspected
Hendra or Nipah virus infected patient from an endemic to a non-endemic area. In these circumstances,
it is essential to minimise the risk to those who come into contact with the patient as part of their work
and to the general public health of the receiving country. Normally the air evacuation procedure of a UK
national infected with Hendra or Nipah virus would be initiated by the Foreign and Commonwealth
Office. The decision to evacuate would be taken in consultation with the DH, CDSC and those
responsible for moving the patient.
8.
If a case of suspected Hendra or Nipah virus infection is notified to a Port Health Authority, or if the
Port Medical Officer has reason to suspect Hendra or Nipah virus infection in a crew member or
passenger of an aircraft or ship, action should be taken to assess the patient and to transfer them to
appropriate isolation facilities in the same way as if the patient were already in the country. If necessary
the powers provided by the Public Health (Aircraft) Regulations 1979 or the Public Health (Ships)
Regulations 1979 may be used.1
1
22
In Northern Ireland the Public Health (Ships) Regulations (Northern Ireland) 1971 and the Public Health (Aircraft) Regulations
(Northern Ireland) 1971 apply.
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Isolation Procedures and Facilities
APPENDIX 4
Isolation Procedures and Facilities
Suspected cases
1.
Suitable protocols for standard isolation procedures, including the use of universal precautions should be
in place. In addition, a number of further precautions are necessary when handling a patient suspected of
being infected with Hendra or Nipah virus.
2.
The isolation facility should be part of a specialist infectious disease unit, sited in an area away from
general circulation, or form part of a separate isolation building. The general public must be excluded
from the area when the facility is in use.
3.
The facility should be staffed by individuals trained in the management of infectious disease. Access
must be restricted to authorised personnel, and a register of all personnel, including clinical, non-clinical
and maintenance staff, entering the Unit should be kept. All authorised personnel must receive
appropriate training and instruction. Information on legal requirements is included in Appendix 8.
4.
Suitable protective clothing to wear over normal clothing, including face and eye protection (e.g. visors)
must be made available. Suitable showering and changing facilities for staff, if contaminated, must be
provided.
5.
A wash basin that can be operated without being touched by hand should be provided, and showering
facilities for staff should be available en route from the Unit to ‘clean’ areas.
6.
The unit must be easy to clean. Floor, wall and other surfaces should be impervious to water, and
resistant to damage from disinfectants.
7.
If radiology or other special investigations are necessary, these should be carried out, if possible, at the
patient’s bedside, after consultation with the Infection Control Doctor.
8.
Crockery and cutlery, if not disposable, should be washed in the patient’s cubicle.
9.
In general, patients should, if able, use an en suite bathroom. Where this is not possible, there should be
protocols for the disposal of excreta.
10.
All waste materials, some of which may be heavily soiled, should be made safe to handle before disposal.
Special arrangements for disposal of waste, including handling, disinfection and access to an autoclave,
should be in place. Guidance on the decontamination of clinical waste is included in Appendix 7.
Confirmed cases
11.
Confirmed cases should be cared for in a HSIDU. The following measures are required additional to
those already listed for suspected cases above. The extent of these additional requirements will depend
on whether the patient is accommodated in a patient bed isolator or in an open room. An open room
should only be used in an emergency, if a patient bed isolator is not immediately available, or in an
outbreak situation.
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Hendra Virus and Nipah Virus
12.
All authorised personnel should receive regular (at approximately 3 monthly intervals) training in use of
the HSIDU, including admitting procedures, patient management, specimen handling etc.
Patient Bed Isolator
Structural requirements
13.
Exhaust air from the patient bed isolator should be HEPA-filtered and then discharged direct to outside
air or via a “thimble” system into the main HEPA-filtered exhaust system.
14.
An autoclave must be installed within the HSIDU.
15.
It is strongly recommended that an incinerator should be available on site. This should either be
dedicated, or, if used for other purposes, special arrangements should be made to transport material for
disposal safely, under direct supervision. Items should be double wrapped or otherwise safely contained.
16.
There must be clear segregation of ‘clean’ and ‘dirty’ areas e.g. by means of a barrier.
17.
There must be clearly defined procedures, (including disinfection protocols), for the admission of the
patient to the isolator.
18.
All waste materials from the patient must be autoclaved or incinerated in an approved incinerator. This
includes effluent from the patient’s wash basin and showers, which may be solidified by absorbent gel
and bagged for incineration, unless effluent holding/treatment tanks are installed.
19.
Disposable linen should be used.
20.
Other facilities
In addition, it is expected that designated HSIDUs would have:
Operational policies
21.
24
•
A clean administrative area with adequate storage rooms;
•
Changing rooms and shower rooms for staff, which should have direct access to the unit;
•
Facilities for the disinfection of ambulances, and shower and changing facilities for ambulance
staff, if those for HSIDU staff are not accessible;
•
Negative pressure HEPA-filtered ventilation of ‘dirty’ areas.
In the event that no patient isolators are available, contingency plans would be implemented for the
designated HSIDUs to make use of open room facilities.
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Isolation Procedures and Facilities
Local policy and procedures for isolation facilities
22.
There should be detailed written operational policies available covering all activities in the Unit
including:
•
informing high security infectious disease laboratories of possible future work on specimens
suspected of containing Hazard Group 4 agents;
•
notifying the relevant authorities when confirmed or suspected cases are admitted;
•
maintaining a register of staff;
•
following-up of all staff contacts;
•
disinfection procedures for equipment both whilst in operation and following a patient’s stay in
the Unit;
•
staff training prior to their undertaking duties in the Unit and subsequent training exercises;
•
providing members of staff with information about the individual patient, and the infectious
risks and appropriate precautions required;
•
informing external staff entering the Unit who may also be exposed, e.g. ambulance staff, of the
appropriate procedures;
•
safe transport of patients;
•
safe transport of specimens;
•
safe disposal of waste;
•
post-mortem investigations (if performed in the Unit);
•
keeping a regularly updated list of appropriate telephone numbers, which should be available
to staff;
•
evacuation in the event of a fire or other emergency;
•
conducting full-scale practice exercises (e.g. twice yearly) so as to check equipment and
operational arrangements;
•
maintaining staffing levels for the HSIDU and arrangements for a support pool of specifically
trained staff.
25
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Hendra Virus and Nipah Virus
APPENDIX 5
The Carriage of Dangerous Goods
Transport within hospitals or laboratories
1.
Specimens should be transported within hospitals or laboratories ‘by hand’ by a responsible person.
Vacuum-tube systems should not be used.
Transport to a HSID laboratory
2.
Infectious substances are defined as “dangerous for transport” under the Carriage of Dangerous Goods
(Classification, Packaging and Labelling) and Use of Transportable Pressure Receptacles Regulations 1996.1
3.
Infectious substances are those known, or reasonably expected, to contain pathogens. These include
biological products, diagnostic specimens, genetically modified micro-organisms (GMMs)/genetically
modified organisms (GMOs) and wastes. Pathogens are defined as micro-organisms (including bacteria,
viruses, rickettsia, parasites, fungi), or recombinant micro-organisms (mutant or hybrid), that are
known, or reasonably expected, to cause infectious disease in animals or humans.
4.
WHO criteria are used to classify pathogens into four risk groups. The likelihood of the presence of
pathogens in a particular risk group within the goods, determines whether the goods are dangerous for
carriage (e.g. goods containing only pathogens in risk group 1 are not dangerous for carriage).
5.
Hazard Group 4 specimens cannot be sent by post due to Post Office conditions of carriage. A specified
courier with communication links between the sending and receiving establishments should be used.
6.
The Regulations (which apply to road and rail carriage) require that before substances are transported,
the consignor has to:
•
identify the substance (classification);
•
suitably package the substance;
•
properly label the package;
•
provide information to the vehicle operator/carrier.
7.
Policies for the transportation of specimens between hospitals and laboratories (e.g. hospital to HSID
laboratory, or HSID laboratory to a Containment Level 4 laboratory) should be agreed between the
sender and the recipient.
8.
At the receiving laboratory, the person in charge should be informed of the arrival of the specimen, the
suspected diagnosis and the level of suspicion. The container used for transportation should be
disinfected or incinerated after use.
1
26
In Northern Ireland the Carriage of Dangerous Goods (Classification, Packaging and Labelling) and the Use of Transportable Pressure
Receptacles Regulations (Northern Ireland) 1997 apply.
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The Carriage of Dangerous Goods
9.
10.
11.
12.
2
3
Packaging
The packaging must comply with the standard consistent with the classification of its contents.
For infectious substances this includes:
•
inner packaging made up of a watertight primary receptacle;
•
watertight secondary packaging, and enough absorbent material between the two to absorb the
contents of the primary receptacle if it were to break;
•
outer packaging of suitable strength, mass and capacity.
Labelling
Packages must be labelled with the following:
•
the proper shipping name of the goods;
•
the UN number;
•
the specified main danger sign.
Information for the carrier
The consignor must provide the following information to the carrier:
•
What is being carried, i.e. name, UN number and classification;
•
Where it came from (name & address);
•
Where it is going (name & address);
•
How much is being carried;
•
Any extra information necessary to determine the transport category of the items and actions
necessary in the event of an emergency.
There are exemptions from the main vehicle related aspects of the Regulations for smaller amounts
of substances in risk groups 2 & 3,2 but no exemptions for any amounts of substances in risk
group 42, which are also subject to additional controls under COSHH Regulations.3
Advisory Committee on Dangerous Pathogens (1995). Categorisation of biological agents according to hazard and categories of
containment. Fourth edition. HSE Books (ISBN 0717610381).
Control of Substances Hazardous to Health (COSHH) Regulations (1999). (ISBN 0110820878). In Northern Ireland Control of
Substances Hazardous to Health (COSHH) Regulations (Northern Ireland) 2000 apply.
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Retrieval of specimens
13.
If a patient, from which samples have already been sent, becomes suspected of Hendra/Nipah virus
infection, it should be the responsibility of an identified individual, such as the CCDC or Infection
Control Doctor, to ensure that specimens:
•
are located quickly; and
•
are appropriately labelled, packed and stored prior to transportation to a HSID laboratory
(see Appendix 2);
or
•
made safe by autoclaving or incineration.
14.
The identities of those who had contact with such specimens should be ascertained and recorded, taking
particular note if any mishap had occurred. Local codes of practice should specify procedures to follow
in such an event, and the disinfectants to be used for dealing with any spillages.
15.
The nominated individual (CCDC or the Infection Control Doctor) should liaise with the Infection
Control Doctor of any hospitals involved, the Regional Epidemiologist/CDSC and the Department
of Health.
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Laboratory Investigations
APPENDIX 6
Laboratory Investigations
1.
To preserve the life of the patient, general hospitals without immediate access to a High Security
Infectious Disease (HSID) laboratory may be obliged to conduct emergency tests to manage critically
ill patients. These arrangements are not intended for continuing patient management. In such
circumstances, advice should be sought of HSID specialists at an early stage, to agree on what emergency
tests are required (none of which should involve or allow replication of the virus). Risks to hospital and
laboratory staff must be minimised.
2.
As specimen taking and handling are the most vulnerable activities likely to lead to mishap and crossinfection, specific policies should be adopted:
•
Tests should be kept to a minimum;
•
Information, instruction and training must be made available, and be appropriate to the
procedures involved;
•
The principles of COSHH must be applied.
3.
Most importantly, the transfer of patients to a HSIDU should not be delayed where infection with
Hendra or Nipah virus is a strong possibility.
4.
Material for transport to a HSID laboratory must be packaged according to instructions provided by
the receiving laboratory. Before any specimens are sent, there should be discussion between the patient’s
clinician, the Infection Control Doctor, and the laboratory microbiologist, to ensure that the appropriate
Containment Level for laboratory investigations is agreed. Specimens must be clearly labelled.
5.
Laboratory procedures MUST involve a full risk assessment of each stage, and should include:
6.
•
inherent risks associated with the chosen techniques (i.e. potential for damage to gloves,
risk of spillage, etc.);
•
recommendations with respect to personnel involved – including grade, levels of training,
medical surveillance measures;
•
disposal of all waste material;
•
decontamination of equipment.
The laboratory must control any procedures that vary from those used in routine investigations,
to assure validity of results.
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7.
8.
1
30
Protocols should be drawn up in advance. It is strongly recommended that these include advice that:
•
air tube systems should not be used for the transport of specimens;
•
any automated blood counting machines and chemistry analysers, used for emergency tests,
should operate in a closed system, and the effluent from the machine should be discharged
within the laboratory drainage system as recommended by the manufacturer.1 Machines should
be flushed with disinfectant after the specimen is processed;
•
where centrifugation is needed, sealed buckets should be used, which should only be loaded and
opened in a suitable Class I or Class III safety cabinet;
•
automated blood culture systems should not be used;
•
blood grouping and cross-matching tests for transfusion, pose particular infection control
problems, and should be avoided – if urgently required, blood group O Rhesus negative
should be used;
•
full and proper records should be kept. These should include records of people who handle
these specimens. They should be made available to the CCDC, on request.
Especially hazardous and difficult procedures to control include:
•
the examination of unfixed liquid samples (e.g. cerebrospinal fluid);
•
the inoculation of body fluids into analysers, culture media etc.;
•
the disposal of all relevant waste material, particularly liquid waste.
Health Services Advisory Committee (1991) Safe Working and the Prevention of Infection in Clinical Laboratories. HMSO
(ISBN 0118854461).
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Clinical Waste
APPENDIX 7
Clinical Waste
1.
Detailed guidance on the handling and safe disposal of clinical waste is given in the document
‘Safe Disposal of Clinical Waste’ issued by the Health Services Advisory Committee.1
2.
Clinical waste is defined in the Controlled Waste Regulations 19922 as being:
•
Any waste which consists wholly or partly of:
–
human or animal tissue;
–
blood or other body fluids;
–
excretions;
–
drugs or other pharmaceutical products;
–
swabs or dressings;
–
syringes, needles or other sharp instruments;
which, unless rendered safe, may prove hazardous to any person coming into contact with it.
AND:
•
3.
Any other waste arising from medical, nursing, dental, veterinary, pharmaceutical or similar
practice, investigation, treatment, care teaching or research, or the collection of blood for
transfusion, being waste which may cause infection to any person coming into contact with it.
Clinical Waste is categorised according to its risk as follows:
•
GROUP A – Identifiable human tissue, blood, animal carcasses and tissue from veterinary
centres, hospitals or laboratories. Soiled surgical dressings, swabs and other similar soiled waste.
Other waste materials, for example from infectious disease cases, excluding any in Groups B-E.
Identifiable human tissue is Group A clinical waste, unless it has been rendered safe and noninfectious,
but it remains an offensive waste, and must be disposed of by incineration at all times.
1
2
•
GROUP B – Discarded syringe needles, cartridges, broken glass and any other contaminated
disposable sharp instruments or items.
•
GROUP C – Microbiological cultures and potentially infected waste from pathology
departments and other clinical or research laboratories.
•
GROUP D – Drugs or other pharmaceutical products.
Safe Disposal of Clinical Waste. HSAC (1999). HSE Books (ISBN 0717624927).
The Controlled Waste Regulations (1992). SI 1992/588. HMSO (ISBN 0110235886). In Northern Ireland the Waste Collection and
Disposal Regulations (Northern Ireland) 1992. SR 1992/254. HMSO. (ISBN 0337108544).
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•
GROUP E – Items used to dispose of urine, faeces and other bodily secretions or excretions
which do not fall within Group A. This includes used disposable bed pans or bed pan liners,
incontinence pads, stoma bags, and urine containers.
Clinical waste disposal
4.
Clinical waste containers must be capable of holding the waste without spillage, and waste bags
conforming to the required NHS standard should be used.
5.
All clinical waste should be disposed of by means of incineration.
6.
If clinical waste is to be transported off site for disposal, the Carriage of Dangerous Goods (Classification,
Packaging and Labelling) and Use of Transportable Pressure Receptacles Regulations 19963 require the
proper classification of clinical waste. The following are considered as dangerous for carriage:
•
any infectious biological waste;
•
any related swabs and dressings from hospitals, clinics, surgeries or laboratories;
•
pharmaceuticals which are toxic, or have flammable or hazardous properties;
•
any infectious waste known or likely to be contaminated with pathogens in risk groups 2, 3,
or 4; and
•
“sharps”.
7.
Clinical waste for transporting off site must be labelled with the correct UN number; UN2814 if human
waste, or UN2900 if animal waste.
8.
Microbiological cultures and pathology waste will normally have been sterilised in accordance with
HSAC guidance, in which case it will not be dangerous for carriage.
3
In Northern Ireland the Carriage of Dangerous Goods (Classification, Packaging and Labelling) and the Use of Transportable Pressure
Receptacles Regulations (Northern Ireland) 1997 apply.
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Health and Safety Law
APPENDIX 8
Health and Safety Law
The Health and Safety at Work etc. Act 1974 (HSWA)
1.
All work except domestic service is subject to regulation under the Health and Safety at Work etc. Act 1974.1
2.
Employers have general duties to ensure, so far as is reasonably practicable, the health, safety and welfare
at work of employees, and to conduct their undertakings in such a way as to ensure, so far as is
reasonably practicable, that other persons who may be affected by the work are not exposed to risks to
their health and safety.
3.
Self-employed people have general duties to conduct their undertakings in such a way as to ensure, so
far as is reasonably practicable, that they and other persons are not exposed to risks to their health and
safety from the work.
4.
Employees have a general duty to take reasonable care for the health and safety of themselves and of
other persons who may be affected by their work, and to co-operate with their employer or any other
person to enable them to comply with any health and safety duties.
The Control of Substances Hazardous to Health (COSHH) Regulations 19992
5.
The COSHH Regulations provide a framework of actions designed to control the risk from a range of
hazardous substances including biological agents. In particular, Schedule 3 specifically refers to biological
agents which include the Hendra and Nipah viruses.
6.
These Regulations require employers to assess the risk of infection for both their employees and others
who may be affected by the work, for example, waste-disposal workers, service engineers and members of
the public. When a risk has been identified, there is a duty to select and properly apply appropriate
prevention or control measures. This may include the use of personal protective equipment, in which
case it must be properly stored, cleaned, maintained and, if found to be defective, repaired or replaced.
In addition, employees must receive suitable and sufficient information, instruction and training about
the risks they may encounter at work. Subject to assessment, there may also be the need to provide
health surveillance for employees.
7.
The assessment of risk required by COSHH must be reviewed regularly and revised when conditions
change, an incident occurs, a deficiency is noted, or if for any other reason, it is suspected that the
assessment is no longer valid.
1
2
3
In Northern Ireland the Health and Safety at Work (Northern Ireland) Order 1978.
In Northern Ireland Control of Substances Hazardous to Health (COSHH) Regulations (Northern Ireland) 2000 apply.
In Northern Ireland the Management of Health and Safety at Work Regulations (Northern Ireland) 1992.
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The Management of Health and Safety at Work Regulations 1992
(MHSWR)
8.
The Management of Health and Safety at Work Regulations3 entail additional duties beyond COSHH.
These include the need for employers to have access to competent help in applying the provisions of
health and safety law; the need to establish procedures to be followed by any worker if a situation
presenting serious and imminent danger were to arise; and the need for co-operation and co-ordination
where two or more employers or self-employed persons share a workplace.
Local safety policies and codes of practice
9.
Employers must have a health and safety policy and undertakings with five or more employees must
record their arrangements for health and safety. While the policy statement may deal in only general
terms with an employer’s intent to develop and maintain a safe working environment, it could make
reference to more specific information on the arrangements for working safely day-to-day which is
contained in local codes of practice. Employers have a responsibility to make the policy and codes freely
accessible, either by putting them on display or by individual issue. All staff, including all newcomers
and temporary workers, must be made aware of them.
Information, instruction and training of employees
10.
There is the need to ensure a clear understanding by all employees of any identifiable risks to their health
arising from work, and the actions to be taken in dealing with situations in which exposure may occur.
Under COSHH, employees must receive suitable and sufficient information, instruction and training on
the risks and precautions to be taken. Under MHSWR, they must receive comprehensive and relevant
information on the risks and preventative and protective measures, together with adequate health and
safety training. The local codes of practice may form part of this process, but thorough instruction on
day-to-day application is needed in order to make the local codes of practice work effectively.
Consultation with employees
11.
Employers have a duty to consult employees on health and safety matters. The Safety Representatives
and Safety Committees Regulations (1977),4 as amended, require employers to consult safety
representatives appointed by any trade unions they recognise. Under the Health and Safety
(Consultation with Employees) Regulations 1996,5 employers must consult any employees not covered
by the 1977 Regulations. Further information and details of additional guidance can be found in the
leaflet ‘Consulting employees on health and safety: A guide to the law’ available from the HSE.
Health surveillance
12.
4
5
34
Where it is appropriate for the protection of the health of employees, both MHSWR and COSHH require
that employees are under suitable health surveillance. Under MHSWR, health surveillance must be
provided as appropriate, having regard to the risks identified by the risk assessment. Under COSHH,
health surveillance must be provided where an identifiable disease or adverse health effect may be related to
the exposure, where there is a reasonable likelihood that the disease or effect may occur under the particular
conditions of work, and where there are valid techniques for detecting indications of the disease or effect.
In Northern Ireland the Safety Representatives and Safety Committees Regulations (Northern Ireland) 1979.
In Northern Ireland the Health and Safety (Consultation with Employees) Regulations (Northern Ireland) 1996.
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Health and Safety Law
13.
A health record, as defined in the Appendix of the COSHH Regulations, should be set up and maintained
and, where appropriate, a list kept of those exposed (see para 11 of Schedule 3 of COSHH). Reference
should be made to Regulation 11(3), Schedule 3, the COSHH general Approved Code of Practice at paras.
92, 96 and 97 and paras. 23 to 25 of the Approved Code of Practice on biological agents.
The Reporting of Injuries, Diseases and Dangerous Occurrences
Regulations 1995 (RIDDOR)6
14.
The current Regulations are designed to provide a national record of certain types of injury, diseases and
dangerous occurrences that might jeopardise the health and safety of workers. There is a requirement in
RIDDOR for employers to report ‘acute illness which requires medical treatment where there is reason
to believe that this resulted from an exposure to a biological agent or its toxins’.
15.
Employers must also report ‘any infection reliably attributable to the performance of ’ particular work,
specified as being ‘work with micro-organisms; work with live or dead human beings in the course of
providing any treatment or service, or in conducting any investigation involving exposure to blood or
body fluids; work with animals or any potentially infected material derived from any of the above’.
There is also a duty to report any ‘accident or incident which resulted, or could have resulted, in the
release or escape of a biological agent likely to cause severe human infection or illness’.
6
In Northern Ireland the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations (Northern Ireland) 1997.
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