الحمى القرمزية هو مرض التي يمكن أن تحدث نتيجة لمجموعة A العقدية.
Scarlet fever is a disease that can occur as a result of a group A Streptococcus (group A strep) infection. The signs and symptoms include a sore throat, fever, headaches, swollen lymph nodes, and a characteristic rash. The rash is red and feels like sandpaper and the tongue may be red and bumpy. It most commonly affects children between five and fifteen years of age. Scarlet fever affects a small number of people who have either 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 characteristic rash is due to the erythrogenic toxin, a substance produced by some types of the bacterium. The diagnosis is typically confirmed by culturing the throat.