Occupational Health for Wildlife Handlers : Occupational Health for Wildlife Handlers M. A. Stevenson, DVM, PhD, DACVS
Director and Attending Veterinarian
The University of Montana-Missoula
Occupational Health : Occupational Health Why now?
Mandatory for UM to maintain animal research program accreditation
Why us?
Everyone listed on an AUP must and any one else interested may participate
Staying Safe : Staying Safe Training
Knowledge
Awareness
Co-workers
Basic Safety Principles : Basic Safety Principles Use appropriate PPE
Gloves, coveralls, washable boots, eye protection, mask or respirator
Good hygiene especially hands
Protect human food and water
Proper use of sharps containers
Communicate with your team
Please do not kiss the animals!
Early Reporting of Injury : Early Reporting of Injury Absolutely imperative to inform
Direct Supervisor
Principal Investigator
Co-workers when in remote field areas
Any unusual symptoms seek medical help immediately
Best defense is a good offense Provide a complete history to assist physicians
Rabies : Rabies Rhabdovirus
Fatal if no treatment or vaccine protection
Infects all warm-blooded mammals
Sylvatic rabies wildlife in life cycle
Ole Yeller
Photo credits - CDC “Mad” Rabies
Rabies : Rabies “Dumb” rabies
Wildlife
Lose fear of humans
Unusually “friendly”
Uncharacteristic places
Uncharacteristic times of day
Neurological signs
Photo credits - CDC Rabid fox
Rabies : Rabies Wildlife reservoirs in US in 2001
Raccoons (38%)
Skunks (30%)
Bats (17%)
Foxes (6%)
Photo credits - CDC Silver-haired bat
Rabies Incidence in U.S. : Rabies Incidence in U.S.
Rabies Transmission : Rabies Transmission Animal bites (virus in saliva)
Contamination of broken skin
Aerosol in bat caves
Corneal, liver, kidney transplant from infected donor
1-2 human cases/year in U.S. most often bat-associated
Rabies Clinical Signs : Rabies Clinical Signs 75% humans ill < 90 days after bite wound
Nausea, vomiting, headache
Tingling and pain on side of body where bite located
Furious and paralytic forms
Cause of death usually respiratory failure during paralytic phase CDC Negri bodies – large pink inclusions in cytoplasm of brain cells – diagnose Rabies
Rabies Prevention : Rabies Prevention Avoid close contact with wild animals exhibiting unusual behavior
Consider pre-exposure immunization if work is high-risk
Report animal bites immediately: post-exposure treatment should start within 24 hours
Hantavirus : Hantavirus Hemorrhagic fever with renal syndrome (HFRS)
1993 - Hantavirus pulmonary syndrome (HPS)
Sin Nombre virus
Wildlife reservoir - Peromyscus maniculatus CDC CDC
Sin Nombre Incidence in U.S. : Sin Nombre Incidence in U.S.
Sin Nombre Transmission : Sin Nombre Transmission Aerosol of deer mouse urine or feces
Contaminated hands mucous membranes
Contaminated food
Bite transmission rare
30-35% fatality rate
Sin Nombre Clinical Signs : Incubation 9 to 33 days
High fever, malaise, muscle or joint aches, nausea, vomiting, diarrhea, headaches, respiratory distress, cough Sin Nombre Clinical Signs Early stage of disease Middle stage of disease CDC CDC
Sin Nombre Prevention : Sin Nombre Prevention Personal protective equipment
Gloves, coveralls, boots
Work upwind of animals
Work in the sun, if possible
Wear a respirator
Fit-test through Environmental Health & Risk Management
Plague : Plague Yersinia pestis
Nonmotile, Gram – rod
“Black Death”
3 forms (mortality):
Bubonic
Septicemic (5-50%)
Pneumonic (20%) Gangrene of fingers – a complication of plague CDC
Plague : Plague > 200 species rodent reservoirs: prairie dogs, rats, marmots, hares, chipmunks, ground squirrels
Xenopsylla cheopis rat flea – regurgitates up to 20,000 plague bacteria from “blocked” gut Prairie Dog CDC CDC
Plague in Animals : Plague in Animals Pin-point hemorrhage petechiae
Swollen lymph nodes
Respiratory disease
Photo credits - CDC
Plague Transmission : Plague Transmission Bites of infected rodent fleas
Entry into breaks in skin when handling infected rodents or rabbits; wild carnivores that eat infected prey
Domestic cats highly susceptible – aerosol or handling
Dogs and cats can carry rat fleas
Plague Clinical Signs : Plague Clinical Signs Illness 2-6 days after infection
Swollen lymph gland, fever, chills, headache, extreme exhaustion
Photo credits - CDC
Plague Clinical Signs : Plague Clinical Signs Cough, bloody sputum, increased heart rate, shock, DIC
Gangrene of fingers and toes 1 month after finger amputation for gangrene CDC
Plague Prevention : Plague Prevention Prevent flea infestation
Handle wild rodents with appropriate PPE
Do not handle wild rodents with petechial hemorrhages
Four Corners area of the US high incidence
Tularemia : Tularemia Francisella tularensis
Aerobic, gram - coccobacillus
> 10 organisms
1.4% fatality rate
Arthropods in life cycle Rhipicephalus sanguineus
“Brown dog tick” CDC
Tularemia Transmission : Tularemia Transmission Bites by infected arthropods
Ticks
Handling infectious tissues
Contaminated food, water, soil
Inhalation of infective aerosols
No human to human transmission
Tularemia Clinical Signs : Tularemia Clinical Signs Fever, headache, chills, body aches (low back), nasal discharge, sore throat
Substernal pain, cough, anorexia, weight loss, weakness CDC CDC
Tularemia Prevention : Tularemia Prevention Personal protective equipment when skinning hares or rodents
Check for ticks daily & remove
Use repellants if possible Wild hare – common culprit for disease transmission to hunters from bare-handed field skinning CDC
West Nile Virus : West Nile Virus Flavivirus
1999 - in US
Horses & humans encephalitis
Bird reservoirs: corvids
Spread by mosquitoes Ochlerotatus japonicus CDC CDC
WNV Clinical Signs : WNV Clinical Signs Incubation 3-14 days
80% infected humans show no symptoms
20% mild symptoms: fever, headache, body aches, nausea, rash
1 in 150 infected severe disease (e.g., stupor, coma, convulsions, paralysis)
West Nile Virus in the U.S. : West Nile Virus in the U.S.
West Nile Virus Prevention : West Nile Virus Prevention Long-sleeved shirts and long pants, when possible
Bug Tamer™ apparel (Shannon Outdoors, Inc)
Mosquito repellant – DEET for skin
Avoid dusk to dawn hours outside
Avoid areas of standing water
http://www.cdc.gov/niosh/topics/westnile/recout.html
Q Fever : Q Fever Coxiella burnetti
Sheep, goats, cattle
1 organism can cause disease
Placental tissues
Spread by
Aerosol
Hands CDC CDC
Q Fever Clinical Signs : Q Fever Clinical Signs 50% infected get ill in 2-3 weeks
30-50% infected get pneumonia
Headache, malaise, muscle aches, confusion, GI signs, weight loss, hepatitis
1-2% fatality rate
Chronic infection endocarditis
65% chronic cases end in death
LCM : LCM Lymphocytic choriomeningitis virus
5% Mus musculus in US; wild mice; pet hamsters
Saliva, urine, feces of infected rodents
Mucous membranes, broken skin, bites Hamster Peromyscus sp.
LCM Clinical Signs : LCM Clinical Signs Humans showing illness signs 8-13 days post-infection
Early: biphasic fever, malaise, muscle aches, headache, nausea, vomiting
Later: headache, stiff neck, confusion, neurological signs
Early pregnancy: abortion or fetal birth defects
Fatality rate < 1%
Slide37 : The University of Montana-Missoula
Occupational Health and Safety Program Participant Capture Employee/Animal User IACUC reviews AUP Visitor Annual Training Sessions “Right to Know” Risk Assessment by OH&S Physician (questionnaire review, facility assessment, novel project assessment, feedback to IACUC) RSC IACUC Coordinator IBC Medical surveillance warranted Procedures/policies to minimize risk Annual Policy Reminder to Dept. Chairs & PIs IACUC No medical surveillance warranted Annual Medical Surveillance