Animals and Allergens

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

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

Risks Associated with the Agent Used Potentially biohazardous agents 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 agent or infected tissue

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

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

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

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

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

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

Containment Caging Systems Microisolator Cage 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

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

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

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

Special Animal Housing Situations Barrier colonies 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 Isolation colonies  Extensive SPFs and defined flora animals  Gnotobiotes (an entirely different animal!)

Zoonoses Zoonotic disease: A disease of animals that can be transmitted under natural conditions and cause disease in humans 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

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

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

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

Control of Zoonoses Get information on species and agent Get information on species and agent Quarantine animals prior to use Quarantine animals prior to use Use Engineering controls Use Engineering controls  facility construction and secondary barriers secondary barriers Consider the need for containment caging 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

Laboratory Acquired Allergies (LAA) Significant occupational disease Significant occupational disease Affects >30% of all personnel working with animals Affects >30% of all personnel working with animals No minimum safe exposure levels to allergens have been established No minimum safe exposure levels to allergens have been established Animal allergens found in hair, dander, urine, saliva, serum 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

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

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

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

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