A streptococcus rash is a rough, red rash that begins around the neck and chest and spreads from there to the rest of the body within one to two days, according to WebMD. A rash resulting from streptococcal bacteria is called scarlet fever.
Strep throat that is caused by the bacteria group A beta-hemolytic streptococcus can cause a scarlet fever rash, according to WebMD. The rash most often occurs in strep throat patients between the ages of 2 and 10. In addition to the rash, patients may experience a high fever, with light-colored spots appearing on the tongue and tonsils. Patients may have swollen lymph nodes and a sore throat, leading to difficulty swallowing. Other possible symptoms include nausea and vomiting, headaches and general aches throughout the body.
Doctors treat scarlet fever with antibiotics, according to WebMD. With proper treatment, scarlet fever begins to heal in about a week. As the rash begins to fade, the skin may peel, and bright red spots may appear on the tongue, a symptom known as strawberry tongue.
Doctors can diagnose scarlet fever by testing for the appropriate strain of streptococcal bacteria with either a throat culture or strep test, according to WebMD. Possible complications of scarlet fever include pneumonia, ear infection, sinusitis and rheumatic complications.