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Scarlet fever — MSRA MCQ

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ModerateInfectious DiseasesScarlet feverMSRA

A 6-year-old boy is brought to general practice with a 24-hour history of fever, sore throat, headache and a widespread erythematous rash. He is drinking adequately and has normal urine output. His temperature is 38.4°C, pulse 108 beats/minute and capillary refill time is 2 seconds. Examination shows tender anterior cervical lymphadenopathy, circumoral pallor, a strawberry tongue and a fine blanching rash with a sandpaper texture over his trunk and groin. He has no cough, coryza, conjunctivitis, vesicles, hypotension or focal soft-tissue pain. He has no drug allergies and can take oral medication. He attends primary school. Which is the most appropriate management today?

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

Reveal the answer and explanation

Correct answer: B — Start a 10-day course of oral phenoxymethylpenicillin, submit a routine notification of suspected scarlet fever, and exclude him from school until 24 hours after antibiotics are started

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

This is clinically typical scarlet fever: fever and pharyngitis followed by a blanching, finely papular ‘sandpaper’ rash, strawberry tongue, circumoral pallor and anterior cervical lymphadenopathy. He is haemodynamically stable, drinking and has no features suggesting invasive group A streptococcal infection requiring emergency assessment. Scarlet fever can usually be diagnosed clinically; treatment should not be delayed for a throat-swab result when the presentation is characteristic. Oral phenoxymethylpenicillin is appropriate first-line treatment in a child without penicillin allergy. Streptococcal infection should be treated for 10 days. Scarlet fever is a routinely notifiable disease in England, and notification is required on clinical suspicion rather than after microbiological confirmation. He should remain away from school until he has received 24 hours of appropriate antibiotics. A is inappropriate because it delays treatment and notification. C uses an inadequate treatment duration and the wrong exclusion criterion. D is a plausible alternative in penicillin allergy, but there is no such allergy here; phenoxymethylpenicillin is preferred. E risks ongoing transmission and omits indicated antibacterial treatment.

Reference: Scarlet fever: guidance and data (Updated 28 August 2025) — https://www.gov.uk/government/collections/scarlet-fever-guidance-and-data Notifiable diseases and how to report them (Updated 19 May 2026) — https://www.gov.uk/guidance/notifiable-diseases-and-how-to-report-them Scarlet fever: symptoms, diagnosis and treatment (2019) — https://www.gov.uk/government/publications/scarlet-fever-symptoms-diagnosis-treatment/scarlet-fever-factsheet