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Pertussis exposure in late pregnancy — MSRA MCQ

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HardInfectious DiseasesPertussis exposure in late pregnancyMSRA

A 31-year-old woman who is 35+5 weeks pregnant contacts her GP after her 4-year-old daughter is diagnosed with PCR-confirmed pertussis. Her daughter’s paroxysmal cough began 8 days ago and she started appropriate antibiotic treatment today. They live together and the patient has provided all of her daughter’s care throughout the illness. The patient is well and has no cough. She received a pertussis-containing booster aged 14 years but has not received pertussis vaccination during this pregnancy. She has no drug allergies, can take oral medication and takes no regular medicines. Which is the most appropriate post-exposure management today?

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

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Correct answer: A — Administer a pertussis-containing vaccine and prescribe erythromycin 500 mg every 6 hours for 7 days

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

This patient requires both vaccination and chemoprophylaxis. She is a household close contact of a confirmed case whose cough began within the preceding 21 days. At more than 32 weeks’ gestation, she is in the UKHSA priority group for people who could transmit pertussis to a vulnerable newborn, provided she has not received a pertussis-containing vaccine within the last 5 years. Her adolescent booster does not meet this criterion, and she has also missed vaccination in the current pregnancy. For pregnant contacts after 32 weeks’ gestation who meet these criteria, UKHSA recommends erythromycin as the preferred chemoprophylactic agent. The regimen is erythromycin 500 mg every 6 hours for 7 days; ideally it should begin at least 3 days before delivery. She should also receive a pertussis-containing vaccine because she is beyond 16 weeks’ gestation and has not received it during this pregnancy. A is inadequate because vaccination does not provide immediate post-exposure protection. B and C use agents that may be alternatives where erythromycin cannot be used, but erythromycin is preferred in late pregnancy. D is inappropriate because co-trimoxazole is reserved for situations where macrolides are contraindicated or not tolerated and is generally avoided in pregnancy when suitable alternatives exist.

Reference: National pertussis guidance for England (May 2026) — https://assets.publishing.service.gov.uk/media/66c4a642808b8c0aa08fa7e7/UKHSA-guidance-on-the-management-of-cases-of-pertussis-during-high-activity-august-2024.pdf National pertussis guidance for England (May 2026) — https://assets.publishing.service.gov.uk/media/66c4a642808b8c0aa08fa7e7/UKHSA-guidance-on-the-management-of-cases-of-pertussis-during-high-activity-august-2024.pdf National pertussis guidance for England (May 2026) — https://assets.publishing.service.gov.uk/media/66c4a642808b8c0aa08fa7e7/UKHSA-guidance-on-the-management-of-cases-of-pertussis-during-high-activity-august-2024.pdf