Epidemiology & Prevention USMLE Step 1 Practice Question
A city with baseline measles incidence of 2-3 cases annually reports 84 confirmed cases this month, predominantly in unvaccinated children (MMR serology positive). Affected patients present with fever (38.9°C), cough, coryza, and characteristic maculopapular rash; SpO2 98% on room air. No complications documented. Public health authorities declare a state of emergency and implement mass vaccination campaigns. Which of the following best describes this epidemiologic event?
Answer choices
- AEpidemicCorrect answer
- BSurveillance bias
- CSecondary attack rate
- DPandemic
- EEndemic occurrence
- FNosocomial transmission event
See the full explanation
Get the correct-answer rationale, why each distractor is wrong, the underlying mechanism, and high-yield associations — plus adaptive practice that targets your weak areas — with a free MedBoardPRO account.