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Aspirin primary prevention — USMLE Step 3 MCQ

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HardPreventive Medicine, Epidemiology, BiostatisticsAspirin primary preventionUSMLE Step 3

A nurse completed a hepatitis B vaccine series but never had postvaccination serologic testing. She sustains a needlestick from a patient known to be HBsAg-positive. Immediate testing shows her anti-HBs concentration is 4 mIU/mL. Which post-exposure plan is most appropriate?

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Correct answer: E — Give one dose of hepatitis B immune globulin and begin revaccination now

The best answer is “Give one dose of hepatitis B immune globulin and begin revaccination now”. Her response to the completed series was previously unknown and the post-exposure anti-HBs is below the protective threshold of 10 mIU/mL. With an HBsAg-positive source, CDC recommends one dose of HBIG plus revaccination as soon as possible. Two HBIG doses without vaccine are reserved for a documented nonresponder after two complete vaccine series.

Reference: CDC Responding to HBV Exposures in Health Care Settings: https://www.cdc.gov/hepatitis-b/hcp/infection-control/index.html