GPAtlas🧭 When to suspect
Suspect scarlet fever in any child – or, less commonly, an adult – presenting with the classic triad of fever, severe sore throat (streptococcal tonsillitis), and a characteristic fine, sandpaper-like rash. It is caused by toxin-producing strains of Streptococcus pyogenes (group A streptococcus, GAS) – the same organism responsible for strep throat and impetigo – in people susceptible to the erythrogenic exotoxin.
Scarlet fever is predominantly a disease of early childhood: around 90% of cases occur in children under 10, most commonly between the ages of 2 and 8 years (peak age 4). Most people over 10 have developed immunity to the toxin. England currently sees roughly 15,000–30,000 cases a year, with notifications rising markedly since 2014. It is a statutory notifiable disease, the diagnosis is clinical, and treatment should be started on clinical suspicion rather than waiting for swab confirmation.
| Phase | Typical features |
|---|---|
| Incubation (1–7 days; usually 2–5) | Asymptomatic; the person may already be infectious. |
| Prodrome (first 12–48 h) | Abrupt fever, sore throat with tonsillitis, headache, malaise, and often nausea or vomiting. Cough and coryza are usually absent. |
| Rash phase (12–48 h after onset) | Fine, blanching, sandpaper rash starting on the neck, chest and abdomen and spreading to the limbs (sparing palms and soles); flushed cheeks with circumoral pallor; strawberry tongue; Pastia's lines in the skin folds. The rash spares the face. |
| Convalescence (after ~1 week) | Desquamation – peeling of the skin, classically of the fingertips, toes and groin – as the rash fades. |
Raise suspicion particularly during the winter and spring peak and where there is a known local outbreak or close contact with a confirmed case of scarlet fever or streptococcal sore throat. Scarlatina (a milder form) may present with the rash and few other symptoms.
Source: NICE NG84 · UKHSA
🔒 Sign up free to read the full topic
You're viewing a free preview. Create a free account to unlock the rest.
Sign up free →Sample topics are open to everyone in the Free Sample Bundle.