Scarlet fever

Scarlet fever should be strongly suspected in a child or adolescent who presents with the triad of sore throat, fever (>100.4°F [>38.0°C]), and a scarlatiniform rash (i.e., a diffuse, finely papular, erythematous rash that feels like sandpaper and blanches with pressure) that starts on the trunk.

Scarlet fever is caused by group A streptococcus (GAS) bacteria and can occur at any age but mainly affects children ages 1-10 years and is most common in those ages 3-6 years. It is uncommon in children <1 year old and in adults.

A rapid antigen detection test (RADT) for GAS from a throat swab should be performed in patients who present with suspected GAS pharyngitis and a scarlatiniform rash or other features suggesting high risk of GAS (e.g., with symptoms or signs of complicated local or systemic GAS infection, a household contact of someone with GAS infection, or with previous rheumatic fever diagnosis). RADT should also be performed in patients age ≥3 years identified as being at risk of GAS pharyngitis using a clinical scoring system such as the Centor or modified Centor (McIsaac) score. Testing is not routinely recommended in children <3 years old or in children with obvious viral clinical and epidemiologic features (e.g., cough, rhinorrhea, hoarseness, mouth ulcers).

Antibiotics (e.g., oral penicillin V or amoxicillin) should be given only to patients with microbiologically confirmed GAS infection (i.e., positive RADT, nucleic acid amplification test, or bacterial culture).

Scarlet fever and the scarlatiniform rash generally self-resolve within 7 days. However, early treatment with antibiotics shortens the intensity and duration of symptoms of the primary GAS infection, reduces the risk of early and late complications such as rheumatic fever and invasive GAS infection, and reduces the risk of onward transmission.

Scarlet fever (scarlatina) is an exotoxin-mediated infectious disease associated with a characteristic erythematous rash of the skin and tongue. It commonly results from GAS infection of the throat or, less commonly, the skin.[1]Centers for Disease Control and Prevention. Clinical guidance for scarlet fever. Feb 2026 [internet publication]. https://www.cdc.gov/group-a-strep/hcp/clinical-guidance/scarlet-fever.html  

​GAS pharyngitis and scarlet fever have similar epidemiology, evaluation, and treatment.

This topic covers scarlet fever in children and adults.