Epidemiology & Prevention USMLE Step 1 Practice Question
Over a 24-hour period, 42 employees at an office develop vomiting and diarrhea after a luncheon. The epidemic curve shows a sharp rise and fall in cases over a single incubation window, with no additional clusters during the week. Which of the following is the most likely explanation for this pattern?
Answer choices
- ALead-time bias from improved case finding
- BPerson-to-person propagated outbreak
- CPoint-source outbreak from a single exposureCorrect answer
- DEndemic disease with seasonal variation
- EHerd immunity failure
- FPropagated outbreak with successive waves over time
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