Bacterial Infections USMLE Step 1 Practice Question
A 24 year old woman returns from a trip to Mexico with 2 days of watery diarrhea, abdominal cramping, and mild nausea. She has no fever, no blood in the stool, and no leukocytes on stool microscopy. Her friends on the same trip developed similar symptoms after eating from street vendors. Which of the following is the most likely causal organism?
Answer choices
- AVibrio cholerae
- BShigella dysenteriae
- CEnterotoxigenic Escherichia coliCorrect answer
- DGiardia lamblia
- EEnterohemorrhagic Escherichia coli
- FCampylobacter jejuni
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