Question

You work in a small family practice in rural Virginia. A man in his early 50s comes in with a complaint of intermittent fever (102— 03°F) and headache for the past two weeks. The physician examines him and takes a history. The only clinical finding is a wound about the size of a quarter on his right thumb. Axillary lymph nodes are swollen and tender. The man says he cut himself while skinning a rabbit three days ago. On the basis of these observations the physician prescribes streptomycin and asks the man to call if his symptoms don’t improve in three days. The physician asks you to draw blood and tells the patient he should return in four weeks for another blood sample. She says there is no need to culture the wound. I. On the basis of the limited information above, the physician has obviously made a diagnosis. What is it? What does it look like when Gram stained? 2. What is the most likely reservoir for the causative organism in this case? 3. Why draw blood twice? 4. Why not culture the wound to look for the bacterium? 5. What are some other common infections that humans acquire from animals? (These are also known as zoonoses.)

Answer 1

Diagnosis- Tularemia or Rabbit fever (Francisella tularensis)

Caused by- handling rabbit meat, insufficiently cooked meat or flies around carrying the germs.

Gram Staining Result- It is a Gram-negative, rod-shaped coccobacillus bacterium.

Reservoir- wild animal (rabbit in this case)

Drawing blood twice- to check if the causative organism is the same and infection is clearing up or not.

The culture was not performed because it was evident from the symptoms and case history that it is tularemia and also this organism is very dangerous and can cause bioterror.

List of Zoonotic diseases- Brucellosis, rabies, anthrax, West Nile virus etc.