Viral Infections USMLE Step 1 Practice Question
A 72-year-old woman in a nursing facility presents with abrupt onset vomiting and profuse watery diarrhea. Multiple residents and staff developed identical symptoms within 24 hours. Vital signs show BP 118/76, HR 102, RR 18, temp 37.8°C, SpO2 98%. Stool culture is negative for bacterial pathogens. She denies recent antibiotic use. Symptoms resolve spontaneously within 48 hours. Several other residents experienced similar self-limited illness. Which organism most likely caused this outbreak?
Answer choices
- AShigella dysenteriae
- BNorovirusCorrect answer
- CVibrio cholerae
- DRotavirus
- EGiardia lamblia
- FEnterotoxigenic Escherichia coli (ETEC)
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