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06/10/2016 Biohazards Objectives • Understand the unique nature and therefore hazards relating to biohazards • Understand the specific variations and procedural additions from the GSOP based on section C of the national guidance for those applicable substances • Overview of GRA 5.4: incidents involving biological hazards Terminology • Pathogenic organisms – Bacteria – Viruses – Protozoa – Fungi and Spores • Toxins 1 06/10/2016 Terminology Term Description Virulence Relative severity of the disease produced Infectivity Relative ease at which microorganisms establish themselves in host, high infectivity – cause disease with few organisms Toxicity Pathogenicity Incubation period Transmissibility Lethality Stability Relative severity of illness or incapacitation produced The capability of an organism to cause disease Time between exposure and appearance of symptoms (time during which organisms are multiplying) Either direct (person to person) or indirect (via a vector – fleas), also refers to ease at which agent is passed Ease at which an organism causes death Stability is affected by environmental factors, including temperature, relative humidity, atmospheric pollution & sunlight Biohazard Definition • any micro organism, cell culture or human endoparasite, including • any that have been genetically modified, that can cause infection, allergy, toxicity or • otherwise create a hazard to human health. Biological Weapons?? • Same thing just with malicious intent – Or accidental…. 2 06/10/2016 • • • • Bacteria Single cell, free living organisms Variety of sizes and shapes (0.01mm length) Some can form spores which are much hardier Many respond to antibiotics • Bacterial cells outnumber human cells – 10:1 • However only 1-3% body mass – 1-3 kg They are all around us!!! 3 06/10/2016 Bacteria Bacteria & Viruses Viruses • Require living cells in order to grow and replicate • Simplest type of microorganism • 100x smaller than bacteria • Generally don’t respond to antibiotic therapy but may be treated with antivirals or immune serum globulins 4 06/10/2016 Virus Bacteria vs Viruses Protozoa • Not really used in modern taxonomy • Unicellular organisms exhibiting animal-like behaviour • Relatively large • Typically parasitic – Malaria – Chagas disease – Sleeping Sickness 5 06/10/2016 Fungi & Spores • There are thousands of species of mould (4,000 to 50,000) • Mould grows in “mats” from microscopic spores • They are everywhere - normally found in buildings at lower levels than outdoors • Some species produce mycotoxins – mycotoxins are used by moulds to compete with other moulds for food sources Toxins • Poisonous substances (chemicals) produced or derived from living plants, animals or microorganisms • They are not living • Effects of exposure typically faster than other biological agents • Examples: Botulinum toxin, Ricin How common are Biohazard incidents? 6 06/10/2016 Where do we find them? Hazard Classification Advisory Committee on Dangerous Pathogens (ACDP) • • • • whether the agent is pathogenic for humans; whether the agent is a hazard to employees; whether the agent is transmissible to the community; and whether there is effective treatment or prophylaxis available Hazard Group Bacillus subtilis 1 unlikely to cause human disease 3 can cause severe human disease and may be a serious hazard to employees; it may Hep B, Rabies spread to the community,Bacillus but thereanthracis, is usually effective prophylaxis or treatment available 2 4 can cause human disease and may be hazard to employees; it is unlikely to spread to Legionella, MRSA the community and there is usually effective prophylaxis or treatment available causes severe human disease and is a serious hazard to employees; it is likely to spread Ebola, smallpox, lassa fever to the community and there is usually no effective prophylaxis or treatment available 7 06/10/2016 Notifications, Control Measures & Hazards • Notification where Biosafety Level (BSL) 4 exists • Higher levels of security • HG3 & 4 buildings required to be under negative pressure • Usually located above ground level • Regular disinfection (what do they use?) • Chemicals • Radiation - sterilization Historical Bioweapons 1346 Plague infected corpses catapulted over the city walls at Kaffa by Tarter army 1940 Japanese drop 5kg of plague-infected fleas on China, 109 plague deaths reported 1763 1984 2001 Alleged the English gave Native Americans smallpox-infected blankets Rajneeshees cult in Oregen contaminates salad bars to affect local elections Letters containing Bacillus anthracis spores sent via mail Sverdlovsk Anthrax Release • 1979 (BWC signed 1972) • 1.2 million people downwind • 77 cases – 66 Deaths • Cause: missing filter 8 06/10/2016 Gruinard Island • Biological warfare test site (1942) • 1981 – Operation Dark harvest • 2001 – SNLA Fungi & Spores Mould becomes a problem when amplification occurs. • Amplification - when the type and number of species and level of mould in an indoor environment become significantly different (often greater) than outdoor levels. • Amplification results when there is an increase in the total number of spores, the establishment of a dominant species, or the increase in population of mould species, different (often greater) than outdoor levels How Can Amplification Occur? Amplification is influenced by environmental conditions: • Light • Water • Humidity • Temperature 9 06/10/2016 Nutrients • Mould uses organic carbon for food • Dwellings contain significant amounts of organic materials such as sheetrock and cellulose ceiling tiles. Any material with organic carbon is a rich source of food for mould and mould growth Temperature • Moulds require a certain amount of heat to grow into a large mat • Areas with little air movement create pockets of heat necessary to facilitate mould growth • Moulds also create heat when metabolizing food (building materials) Water & Humidity • Water is the key or limiting factor to amplification • When mould spores normally in the air, land on wet food sources (e.g. building materials) they grow rapidly, usually within 48 hours. • Prefer humid environments – above 60% 10 06/10/2016 Health Implications of Mould • Some mycotoxins are toxic, carcinogenic and/or teratogenic to humans; some cause serious fungal infections • Not everyone is affected; necessary data is lacking to understand why • In general, individuals with compromised immune systems, asthmatics and those allergic to mould may be more susceptible Septicemia Toxigenic Species • Large number of genus (e.g. Aspergillus) with many toxigenic species (e.g. Aspergillus fumigatus) • Common genus found at cannabis farms: – Stacybotrys – Aspergillus – Cladosporium – Fusarium 11 06/10/2016 Stachybotrys • Only one known species, has two names Stachybotrys atra or Stachybotrys chartarum – labelled by media as “Black Mould” • Produces tricothecene, one of the more deadly mycotoxins, potential biological agent; toxin present in spores; in high enough dose potential to cause bleeding of the lungs and kill highly sensitive individuals (young infants, elderly, immuno-compromised individuals, etc.). • Thrives on water damaged, cellulose-rich building materials (e.g. sheet rock, paper) Aspergillus • Over 185 species; 20 potentially toxic to man; 2nd most common fungal infection requiring hospitalization • Dark green-black in colour, has a fuzzy appearance • Can produce allergic reaction like asthma or severe life-threatening infections • Produces aflatoxin, toxic and one of the most carcinogenic substances known and Ochratoxin which damages kidneys, liver and a suspected carcinogen • People with depressed immune system could develop serious allergies and even contract disease Aspergillosis Cladosporium • Found on decaying plants, food, paint, textiles and fiberglass duct insulation • Dark green to black in front and black on reverse with velvety to powdery texture • Over 30 species of Cladosporium genus • Fungi cause skin lesions, keratitis, nail fungus, sinusitis, asthma and pulmonary infections; edema and bronchospasms may occur as well as pulmonary emphysema from chronic exposure 12 06/10/2016 Fusarium • Common soil fungus found on various of plants; often found in humidifiers, water-damaged carpets and variety of building materials • Human exposure occurs through ingestion of contaminated grains and possibly through inhalation of spores • Produces haemorrhagic syndrome in humans (nausea, vomiting, diarrhoea, dermatitis and internal bleeding); similar to Stachybotrys, produces trichothecene, one of more deadly mycotoxins and zearalenone, a mycotoxin similar to estrogen that targets reproductive organs Penicillium • Common in soil, food, cellulose, grains, paint, carpet, wallpaper, interior fiberglass duct insulation, and decaying vegetation; several species exist • May cause hypersensitivity, pneumonitis, asthma, and allergic alveolitis in susceptible individuals; has been isolated from patients with keratitis, ear infections, pneumonia, endocarditis, peritonitis and urinary tract infections • Can produce Ochratoxin A which is toxic, damaging the kidneys, liver and a suspected carcinogen as well as Verrucosidin, a neurotoxin Effects of Mould 13 06/10/2016 Transportation • UN 2814, 2900, 3373 or 3291 • Category A: – Transported in a form that is capable of causing permanent disability, lifethreatening or fatal disease to human or animal • Category B: – doesn’t meet category for Category A Transportation Labelling & Marking • All substances should be triple packaged and incorporate a waterproof and leak proof system • Everything except HG4 can be posted 14 06/10/2016 • • • • Routes of Entry Skin Contact Puncture wounds & cuts Inhalation Ingestion PPE • Level of PPE determined by: – Nature of biohazard present – Potential of exposure – Presence of biohazard expert • Liquid-tight suit and BA adequate even up to hazard group 4 PPE 15 06/10/2016 Post Exposure Prophylaxis • Varies between hazard – HIV / Hep recommend within an hour of exposure – Anthrax can be longer • Exposure records for HG3 & 4 – 10 years – 40 years (agents with delayed effects) • Recent Ebola victim Identification • Lateral Flow Assay Identification • DSTL have Mobile PCR – Results within an hour – Recurring discussion with NR but no plans for near future 16 06/10/2016 Decontamination • Most die in fire!!! • • • • – Above 60°C Bleach solution (fresh) Virkon, etc Formaldehyde, Chlorine Dioxide Hydrogen Peroxide Vapour (HPV) Biohazard Pre-planning • Contacts and Planning – HG3 & 4 premises must have written plans – HG4 premises must have expert advice at all times • Planning documents should include – Nature of hazards – Extent of hazards – Exact location UK Biohazard sites • 9 Containment Level 4 (CL4) sites – All in south east • • • • • • • Colindale London Pirbright (2x) Warwick Addlestone Potters Bar Porton Down (2x) • 600 Containment Level 3 (CL3) sites 17 06/10/2016 Incidents involving Biohazards • Approach uphill & upwind • “Controlled burn” tactic • Consider impact of potentially infectious run off • Control risk of exposure – PEP? • Specialist decon or just bleach or similar • Records of any exposures and health surveillance monitoring Zoonotic disease outbreaks Ebola 18 06/10/2016 Review • Understand the unique nature and therefore hazards relating to biohazards • Understand the specific variations and procedural additions from the GSOP based on section C of the national guidance for those applicable substances • Overview of GRA 5.4: incidents involving biological hazards 19