Tara Booth, age 12, of McAllen, Tex, for her question:

WHAT CAUSES STREP THROAT?

Strep throat is an infectious disease that mainly hits children between the ages of 5 and 15 years. It is caused by a bacterium called Group A streptococcus.

First symptoms of a strep throat include fever, sore throat, aching muscles and headache. If a person has any of these symptoms, a doctor may take a pus sample from the throat and make a culture. If the patient has strep throat, strep bacteria will grow in the culture.

Doctors use penicillin and erythromycin many times to treat strep throat. Prompt treatment can keep the infection from spreading to the ears and sinuses.

Most patients who receive the correct treatment recover from step throat with no after effects.