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Routine infant immunization — USMLE Step 3 MCQ

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HardPediatricsRoutine infant immunizationUSMLE Step 3

A healthy infant is 15 weeks 2 days old and has received hepatitis B vaccine only. The family now agrees to routine immunization. Which vaccine should not be initiated because the maximum age for the first dose has passed?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: E — Rotavirus vaccine

The best answer is “Rotavirus vaccine”. The first rotavirus dose must be given before age 15 weeks 0 days because of age-dependent intussusception considerations; the final dose is due by 8 months 0 days. The other primary-series vaccines can be started with the CDC catch-up schedule at this age.

Reference: CDC Child and Adolescent Immunization Schedule: https://www.cdc.gov/vaccines/hcp/imz-schedules/child-adolescent-age.html