Scarlet fever, also called scarlatina, is a rash caused by toxins produced by group A streptococcus bacteria. About half the people who get scarlet fever have had a prior streptococcal throat infection.
People with scarlet fever usually have a "sand-paper like" rash which starts on the neck, chest, armpits, elbows, and inner surfaces of the thigh and can spread to the rest of the body. The rash usually peels off after a week, much like skin does after a sunburn. Other symptoms may include fever, chills, sore throat, swollen and red tongue known as strawberry tongue, nausea and vomiting.
Scarlet fever is spread through direct contact with a person who has active streptococcal sore throat. It is spread by droplets through sneezing or coughing. In rare cases, scarlet fever can be spread indirectly by contact with objects used by infected persons.
Scarlet fever can occur at any age but is most common in children ages 5-15. Also at risk are people in crowded environments such as day care or military settings, and people who have been exposed to someone with strep throat or a skin infection caused by certain kinds of streptococcal bacteria. Infection can occur year round but is more common in the spring and fall.
Scarlet fever is diagnosed through medical history and physical exam. A throat culture or rapid antigen test can confirm the diagnosis.
Symptoms can start one to seven days after exposure but usually within 72 hours.
Complications are rare but may include kidney disease and rheumatic fever that could lead to heart damage. Prompt and proper treatment can reduce the possibility of complications.
Antibiotics such as penicillin and erythromycin are used to treat scarlet fever. Treatment is important to prevent serious complications such as rheumatic fever and kidney disease. With proper antibiotic treatment the symptoms of scarlet fever should resolve quickly although the rash may persist for 2-3 weeks.
Early identification and treatment of streptococcal infections with antibiotics can prevent this condition. Avoiding contact with people with sore throats may also decrease the risk. Good personal hygiene, such as covering one's mouth when coughing or sneezing and hand washing, can reduce transmission.
People with scarlet fever can spread the disease to others until 24-48 hours after treatment; infected children and adults may return to school or work after the second day of a course of antibiotic therapy.
Immunity against the scarlet fever rash is usually permanent. Recurring attacks are rare but may occur because of the different forms of the toxin causing this infection.