Which category is NOT among the four most common diseases in contingency operations?

• A. Vectorborne
• B. Tickborne
• C. Diarrheal
• D. Respiratory.

Answer: (B)

The key idea is that disease categories in contingency operations are grouped by transmission route, using broad umbrellas like vectorborne, diarrheal, and respiratory. Tickborne illnesses are transmitted by ticks, which makes them a subset of vectorborne diseases. Since the framework uses a single vectorborne category to cover all tick-, mosquito-, and other vector–transmitted diseases, tickborne would not stand as its own separate category. That’s why tickborne is not among the four main categories.