Animals and Allergens

1. Animals and Allergens

2. Risk Assessment for Work with Research Animals • Risks associated with the research agent used in the animal • chemical, physical, biological • Risks associated with the species of animal used • zoonotic agents • Risks associated with animal maintenance • ergonomic factors, bites, scratches, allergens

3. Risks Associated with the Agent Used • Chemical agents • carcinogens, mutagens • toxic chemicals • anesthetics • Physical agents • radiation • heat • sound

4. Risks Associated with the Agent Used • Potentially biohazardous agents • deliberate use of an infectious agent in animals for research purposes • maintenance of infected animal for duration of experiment • sacrifice, necropsy and harvesting of agent or infected tissue

5. Transmission of Biohazards During Work with Animals Airborne • Release of infectious aerosols by animal by sneezing, coughing • Release during nasal infection or aerosol challenge • Aerosolization from bedding and excreta • During surgical procedures • During birthing

6. Transmission of Biohazards During Work with Animals Direct Inoculation • Needlesticks during injection/inoculation process • Bites and scratches from infected animal

7. Transmission of Biohazards During Work with Animals Direct exposure of mucous membranes (by splash or splatter) • During surgical procedures • During injection • During necropsy

8. Transmission of Biohazards During Work with Animals Indirect transmission and ingestion • From contaminated hands or gloves to mouth • Facial contamination directly from animal • Transfer of parasites by animal handling Indirect transmission with eye or mucous membrane exposure • Dust from bedding • Splash during cage washing • “Dirty” environment

9. Risk Reduction: Containment of Infectious Agent • Containment must include: • Primary containment • Enclosed filtered caging system • Biosafety cabinets • Safety equipment • PPE • Secondary containment • The containment facility • Negative pressurization • Nonrecirculated air supply • Ventilation must consider wellbeing of animal

10. Containment Caging Systems • No Containment • Open (standard) cage • Some Containment • Filter top cage (microisolator cage) • Full Containment • Fully enclosed in ventilated rack

11. Containment Caging Systems • Microisolator Cage • works like a Petri dish • open gaps around lid edge allow limited air exchange • may lead to more labor intensive husbandry due to moisture and ammonia buildup

12. Containment Caging Systems • Individual cages sealed into rack with supplied air under negative pressure • Both supply and exhaust usually HEPA filtered • Ventilation must control humidity and buildup of ammonia

13. Containment Caging Systems • Can install cages in class III biosafety cabinet • Cages are completely contained with glove port access • Very motion-limiting • Transfer in and out may be an issue

14. Containment Caging Systems • BioBubble (Ft. Collins, CO) makes soft-wall ventilated enclosures • Can be containment or barrier style • Large equipment can be surface-mounted in wall

15. Special Animal Housing Situations • Barrier colonies • Special breeds - often immunocompromised, “fragile”, expensive (SCID-Hu, nude athymics) • Transgenics - often even more fragile and expensive (knockouts, microinjected, combos) • Specific pathogen-free (SPF) - bred and raised to be missing certain specific microorganisms • Isolation colonies • Extensive SPFs and defined flora animals • Gnotobiotes (an entirely different animal!)

16. Zoonoses • Zoonotic disease: A disease of animals that can be transmitted under natural conditions and cause disease in humans • Wild caught animals most hazardous • Random source animals (e.g., from a pound) are also a risk • Purpose bred animals pose least risk

17. Animal Macaque monkeys Sheep White mouse Dogs, cats, skunks, raccoons, bats Cattle, NHP Cats Parrots, macaws Chickens Disease Herpes B virus Q fever Hantavirus Rabies Tuberculosis Toxoplasmosis Psittacosis Avian influenza Some Animals and Their Zoonoses

18. Rodent Zoonoses • Rat bite fever (Streptobacillus moniliformis, Spirillum minus) • transmission: direct contact (bites) • Lymphocytic choriomeningitis (LCM, a virus) • transmission: inhalation • Leptospirosis (Leptospira spp.) • transmission: inhalation • Others include ringworm (fungal), scabies (mites, an ectoparasite)

19. Transmission of Zoonoses • Enteric route (fecal/oral) • Salmonella, Shigella, Campylobacter, Giardia, Toxoplasma, Cryptosporidium, Entamoeba, Hepatitis A • Respiratory route • Q fever, Chlamydia, Measles • Skin contact • Ringworm (Tinea), Measles, Monkeypox

20. Get information on species and agent Quarantine animals prior to use Use Engineering controls facility construction and secondary barriers Consider the need for containment caging Use Administrative controls written SOPs and manuals Use PPE additional protection for worker Practice good facility and personal hygiene Provide staff training Control of Zoonoses

21. Laboratory Acquired Allergies (LAA) • Significant occupational disease • Affects >30% of all personnel working with animals • No minimum safe exposure levels to allergens have been established • Animal allergens found in hair, dander, urine, saliva, serum • fel-d-l cat allergen (in saliva and thus on skin) is one of the strongest allergens known for humans

22. Sources of Exposure to LAA • Hair and dander shed from animal • Urine and feces dried in bedding • Particulates shed from bedding material • Animal saliva

23. Routes of Exposure to LAA • Inhalation of airborne allergens • during cage changing • during animal handling • Skin or eye contact • usually indirect by touching skin, eyes • Percutaneous exposure • animal bites (saliva)

24. Risk Factors for Development of LAA • Exposure to allergens • duration • frequency • intensity • Previous allergic conditions • Other predisposing conditions • illness • Immunocompromised • pets

25. LAA: Exposure Control • Engineering Controls • enclosure • dilution ventilation • Administrative Controls • reduce time with animals • reduce density of animals • housekeeping practices • Personal Protective Equipment • respirators and clothing • Medical Surveillance