Epidemiology & Prevention USMLE Step 1 Practice Question
A local health department identifies 12 cases of hepatitis A (ALT 850 U/L, anti-HAV IgM positive) linked to a restaurant over 10 days. Affected patients present with jaundice, fever (38.5°C), and abdominal pain; no cases involve healthcare workers. Most cases consumed raw shellfish from the same supplier 2 weeks prior. Before testing specific menu items, which of the following is the most appropriate immediate next step to help prevent additional cases?
Answer choices
- AWait for culture confirmation before intervening
- BClose the restaurant temporarily and interview cases about common exposuresCorrect answer
- CBegin a case-control study only after 6 months of follow up
- DAssume person-to-person spread and take no action on the food source
- EPublish the names of all infected patients in the newspaper
- FImmediately test all restaurant employees for anti-HAV IgG to identify immune individuals
See the full explanation
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