DVM Zoonotic Diseases and Public Health 2 — Questions and Answers
Question 1: A veterinarian in a rural clinic is bitten by a stray cat. Which rabies post-exposure prophylaxis (PEP) step is MOST critical if the animal cannot be observed?
- Administer rabies immune globulin (RIG) plus vaccine series immediately (Correct answer)
- Administer vaccine series only, starting within 72 hours
- Wait 10 days and observe the cat before initiating PEP
- Administer RIG only, then reassess in 48 hours
Correct answer: Administer rabies immune globulin (RIG) plus vaccine series immediately
When the biting animal cannot be observed or tested, RIG plus the full vaccine series must begin immediately per CDC guidelines.
Question 2: Brucella canis is considered a significant zoonotic risk primarily through which occupational exposure route?
- Ingestion of unpasteurized dairy from infected dogs
- Direct contact with reproductive fluids, aborted fetuses, or placental tissue (Correct answer)
- Inhalation of dried fecal aerosols from kennels
- Vector-borne transmission via dog ticks
Correct answer: Direct contact with reproductive fluids, aborted fetuses, or placental tissue
B. canis is shed in highest concentrations in reproductive tissues and fluids, posing greatest risk during whelping or abortion events.
Question 3: A hunter presents to a veterinarian with an acute febrile illness after skinning wild rabbits in the US. Which organism is the most likely cause?
- Yersinia pestis
- Francisella tularensis (Correct answer)
- Coxiella burnetii
- Borrelia burgdorferi
Correct answer: Francisella tularensis
Francisella tularensis (tularemia) is classically associated with contact with wild rabbits during hunting and skinning activities.
Question 4: Which of the following zoonotic diseases is classified as a CDC Category A bioterrorism agent AND is naturally transmitted from animals to humans?
- Anthrax (Bacillus anthracis) (Correct answer)
- Salmonellosis
- Leptospirosis
- Psittacosis
Correct answer: Anthrax (Bacillus anthracis)
Bacillus anthracis is a Category A bioterrorism agent that naturally infects livestock and can be transmitted to humans via contact, ingestion, or inhalation.
Question 5: A dairy farm worker develops flu-like symptoms, hepatitis, and endocarditis weeks after exposure to parturient cattle. The most likely zoonotic diagnosis is:
- Listeriosis
- Q fever (Coxiella burnetii) (Correct answer)
- Bovine brucellosis
- Campylobacteriosis
Correct answer: Q fever (Coxiella burnetii)
Q fever caused by Coxiella burnetii is strongly associated with parturient ruminants and can progress to chronic endocarditis in some patients.
Question 6: Hendra virus spillover events in Australia primarily involve which reservoir host and which intermediate species?
- Rodents → horses → humans
- Fruit bats (Pteropus spp.) → horses → humans (Correct answer)
- Birds → pigs → humans
- Bats → cattle → humans
Correct answer: Fruit bats (Pteropus spp.) → horses → humans
Hendra virus is maintained in Pteropus fruit bats and spills over to horses, which then serve as amplifying hosts for human infection.
Question 7: A veterinary student develops a painful pustular lesion on the hand after working with sheep at a teaching farm. The causative agent is most likely:
- Parapoxvirus (orf virus) (Correct answer)
- Staphylococcus aureus
- Dermatophilus congolensis
- Bacillus anthracis
Correct answer: Parapoxvirus (orf virus)
Orf (contagious ecthyma) caused by parapoxvirus is a classic occupational zoonosis of sheep and goat handlers, producing self-limiting pustular skin lesions.
DVM Zoonotic Diseases and Public Health 2
A veterinarian in a rural clinic is bitten by a stray cat.
Which rabies post-exposure prophylaxis (PEP) step is MOST critical if the animal cannot be observed?