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Hepatitis B sexual-exposure post-exposure prophylaxis — MSRA MCQ

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ModerateInfectious DiseasesHepatitis B sexual-exposure post-exposure prophylaxisMSRA

A 32-year-old woman attends general practice after her male partner was admitted yesterday with acute hepatitis B. His results are HBsAg positive and anti-HBc IgM positive. She last had unprotected vaginal intercourse with him 5 days ago and they had had unprotected sex several times during the preceding month. She is asymptomatic and has no previous hepatitis B vaccination. She is not pregnant, has no immunosuppression, and has no drug allergies. Your practice can administer hepatitis B vaccine today but does not stock hepatitis B immunoglobulin (HBIG). What is the most appropriate management today?

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

Reveal the answer and explanation

Correct answer: C — Initiate an accelerated hepatitis B vaccine course today and arrange HBIG administration today

Explanation lettering: D = shown as A · A = shown as B · B = shown as C · C = shown as D

This is a significant sexual exposure to a confirmed case of acute hepatitis B. The decisive features are unprotected intercourse and presentation within 1 week of the last contact. UK guidance states that sexual partners of people with acute hepatitis B should receive hepatitis B vaccine and, if seen within 1 week of last contact, HBIG as well. Vaccine should be started immediately and must not be delayed while HBIG is being sourced; HBIG should be given as soon as possible and no later than 7 days after exposure. For post-exposure prophylaxis, an accelerated hepatitis B schedule (0, 1 and 2 months) is used, making B the best answer. A omits HBIG despite eligibility after exposure to acute infection. C correctly includes HBIG but uses the routine rather than post-exposure vaccination schedule. D is unsafe because testing may be undertaken, including baseline HBsAg, but must not delay prophylaxis. E provides relevant risk-reduction advice but fails to deliver time-critical passive and active immunisation. She should also be advised to use condoms and to complete the vaccine course; follow-up testing for infection is appropriate at 6 months.

Reference: Green Book on immunisation: Hepatitis B, chapter 18 (5 February 2026) — https://assets.publishing.service.gov.uk/media/699c8d35e1c6bad1576fbc01/Green-book-on-immunisation-hepatitis-B-chapter_-_05022026.pdf Green Book on immunisation: Hepatitis B, chapter 18 (5 February 2026) — https://assets.publishing.service.gov.uk/media/699c8d35e1c6bad1576fbc01/Green-book-on-immunisation-hepatitis-B-chapter_-_05022026.pdf