Scarlet fever is an illness caused by the same bacteria that cause strep throat
. A person with scarlet fever most commonly develops a sore throat
and rash. This condition is usually seen in people under the age of 18. For unknown reasons, it has become less common in recent years.
Scarlet fever is an illness caused by bacteria called group A streptococcus, the same bacteria that cause strep throat. Group A streptococcus (known as Streptococcus pyogenes) produces a toxin that causes the symptoms. Some people are sensitive to this toxin; others have developed immunity. This is why two people in the same household can have a strep infection, but only one may develop scarlet fever.
Understanding Group A Streptococcus
Group A streptococcus is most familiar to people because it is responsible for strep throat and scarlet fever. Group A streptococcus can also cause:
- Skin infections, such as impetigo (characterized by blisters that may itch)
- Erysipelas (hardened, painful skin lesions with raised borders)
- Cellulitis (inflammation of connective tissue of the skin).
Health experts estimate that more than 10 million mild infections (throat and skin), caused by group A streptococcus, occur every year.
Other more serious infections that group A streptococcus can cause include:
- Bacteremia (blood stream infections)
- Toxic shock syndrome (multi-organ infection)
- Necrotizing fasciitis (flesh-eating disease).
Occasionally, group A streptococcus can also cause pneumonia