American Board of Internal Medicine (ABIM) Certification Practice Exam

What infectious agent is associated with contact or bites from infected animals, particularly cats?

1. Mycobacterium marinum

2. Francisella tularensis

3. Mycobacterium fortuitum

4. Salmonella

The correct answer is: Francisella tularensis

The infectious agent associated with contact or bites from infected animals, particularly cats, is Francisella tularensis. This organism is the causative agent of tularemia, a disease that can be transmitted through direct contact with infected animals or their tissues, bites from infected animals, or through environments contaminated with the bacteria. Cats can be particularly important in the transmission of tularemia due to their hunting behaviors, which may lead them to come into contact with infected rodents or lagomorphs. Mycobacterium marinum and Mycobacterium fortuitum are primarily associated with water-related infections and skin lesions, often linked to exposure to contaminated water or environments, rather than direct animal contact. Salmonella is typically associated with foodborne illness or exposure to reptiles, poultry, and contaminated food, and does not have a strong linkage to animal bites or contact. Thus, Francisella tularensis is the most suitable choice given its direct association with animal bites, particularly those from cats.