Scarlet fever is a disease caused by infection with the group A Streptococcus bacteria (the same bacteria that causes strep throat).
Causes, incidence, and risk factors
Scarlet fever was once a very serious childhood disease, but now is easily treatable. It is caused by the streptococcal bacteria, which produce a toxin that leads to the hallmark red rash of the illness.
The main risk factor is infection with the bacteria that causes strep throat. A history of strep throat or scarlet fever in the community, neighborhood, or school may increase the risk of infection.
The time between becoming infected and having symptoms is short, generally 1 - 2 days. The illness typically begins with a fever and sore throat.
The rash usually first appears on the neck and chest, then spreads over the body. It is described as "sandpapery" in feel. The texture of the rash is more important than the appearance in confirming the diagnosis. The rash can last for more than a week. As the rash fades, peeling (desquamation) may occur around the fingertips, toes, and groin area.
Your symptoms do not go away 24 hours after beginning antibiotic treatment
You develop new symptoms
Bacteria are spread by direct contact with infected people, or by droplets exhaled by an infected person. Avoid contact with infected people.
Bisno AL, Stevens DL. Streptococcus pyogenes. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 198.
Gerber MA. Group A Streptococcus. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 176.
Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.