Scarlet fever

Scarlet fever (also termed scarlatina or scarlatiniform rash) is an infectious disease caused by Streptococcus pyogenes, a Group A streptococcus (GAS) bacterium. The condition represents a toxin-mediated manifestation that typically follows an antecedent streptococcal pharyngeal or skin infection. Classified under ICD-10 code A38 and ICD-11 code 1C1Z, the disease is categorized as a bacterial illness requiring notification in many surveillance systems.

The clinical syndrome begins with sudden-onset sore throat, fever exceeding 39°C, headache, and malaise, often accompanied by nausea, vomiting, and abdominal pain. A characteristic diffuse rash develops one to two days after symptom onset, appearing first on the neck or torso as small flat spots that progress to rough, sandpaper-textured papules spreading to the extremities; the face typically appears flushed with perioral pallor. The oral cavity exhibits distinctive findings including a whitish-coated tongue with prominent red papillae (white strawberry tongue) progressing to a denuded red appearance (red strawberry tongue). On darker-pigmented skin, the rash may be difficult to visualize despite the characteristic sandpaper texture. Complications are divided into suppurative (peritonsillar abscess, cellulitis, mastoiditis, sinusitis) and nonsuppurative forms, with untreated cases at risk for long-term sequelae including kidney disease and rheumatic fever.

Scarlet fever demonstrates a marked predilection for children and young adolescents between five and fifteen years of age, reflecting the epidemiological pattern of group A streptococcal pharyngitis in this age group. The disease develops in a minority of individuals following streptococcal throat or skin infections. Source-backed detail on geographic distribution patterns, seasonal outbreak dynamics, reservoir ecology, and population-level surveillance burden is not yet available from the provided sources.

The causative bacterium spreads primarily through respiratory droplets generated by coughing or sneezing. Transmission may also occur via indirect contact with contaminated objects followed by hand-to-mouth or hand-to-nose exposure. The infectious period and environmental persistence characteristics are not detailed in the available source material.

Children between five and fifteen years of age constitute the primary risk group, reflecting the epidemiology of group A streptococcal pharyngitis transmission in school and household settings. Young children under five years may present atypically with nasal congestion and lower-grade fever, while infants may exhibit nonspecific symptoms including irritability and reduced feeding. Individuals with untreated or inadequately treated streptococcal infections are at risk for developing scarlet fever as a secondary manifestation.

No vaccine exists for scarlet fever. Public health prevention relies on frequent handwashing practices, avoidance of sharing personal items with infected individuals, and maintaining distance from others during the symptomatic period. Antibiotic treatment not only reduces symptom severity and duration but also effectively prevents transmission to contacts and substantially decreases the risk of complications.

Case identification typically requires laboratory confirmation through throat swab culture, as clinical presentation alone may not distinguish scarlet fever from other exanthematous illnesses. Surveillance systems should account for the age-specific predilection (5-15 years) and consider the potential for underdiagnosis on darker skin tones where rash characteristics may be less apparent. The absence of vaccine availability underscores the importance of monitoring antibiotic susceptibility patterns and tracking nonsuppurative complications as indicators of disease burden and treatment adequacy.

1. 1 Wikidata. scarlet fever.
2. 2 Wikipedia. Scarlet fever - Wikipedia.

ICD-10

A38

ICD-11

1C1Z

Total cases

809K

Total deaths

9

Peak month

2019-12

Coverage

1 reporting countries · 2010-01-01 → 2026-04-01