scarlet fever

Scarlet fever, also known as scarlatina and scarlatiniform rash, is an infectious disease caused by Streptococcus pyogenes, a Group A streptococcus (GAS). It most commonly affects children and young adolescents between five and 15 years of age. The signs and symptoms include a sore throat, fever, headache, swollen lymph nodes, and a characteristic rash. The face is flushed and the rash is red and blanching. It typically feels like sandpaper and the tongue may be red and bumpy. The rash occurs as a result of capillary damage by exotoxins produced by S. pyogenes. On darker-pigmented skin the rash may be hard to discern.

Scarlet fever develops in a small number of people who have strep throat or streptococcal skin infections. The bacteria are usually spread by people coughing or sneezing. It can also be spread when a person touches an object that has the bacteria on it and then touches their mouth or nose. The diagnosis is typically confirmed by culturing swabs of the throat.