Epidemiology & Prevention USMLE Step 1 Practice Question
A local health department identifies 12 cases of hepatitis A linked to a restaurant over 10 days. Affected patients present with fever (38.5°C), jaundice, and elevated transaminases (ALT 1,200 U/L). None report bloody diarrhea. Before testing specific menu items, the health inspector learns that 40% of restaurant workers lack hepatitis A vaccination documentation. Which of the following is the most appropriate immediate next step to prevent additional cases?
Answer choices
- ABegin a case-control study only after 6 months of follow up
- BAssume person-to-person spread and take no action on the food source
- CClose the restaurant temporarily and interview cases about common exposuresCorrect answer
- DPublish the names of all infected patients in the newspaper
- EWait for culture confirmation before intervening
- FImmediately vaccinate all restaurant workers and customers without testing for immunity status
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