This page was reviewed or revised on Thursday, October 20, 2011 10:20 AM
Group A Streptococcus (GAS) is a bacteria found in the throats or on the skin of many people. It causes common infections such as a sore throat (strep throat), tonsillitis, scarlet fever and impetigo, a skin infection.
Sometimes, GAS can be found in uncommon places such as blood, fluid around the brain and spinal cord, in the lining of the muscles or in the joints. These GAS infections are called invasive diseases and result in:
About 10%-15% of people carry GAS in their throat without any problems. It can be spread from the nose or throat secretions of a person without symptoms or by a person who is ill with GAS. It is spread when the secretions directly contact the nose or mouth of an at risk person.
Avoid sharing objects or food that involves contact with another person’s nose or throat secretions. It can also spread when a person contacts infected cuts on the skin, such as impetigo. GAS is not spread through the air; infected people are usually not contagious after 24 hours of treatment with antibiotics.
Close contacts of people with GAS have an increased risk of infection. Close contacts are those exposed to nose or throat secretions or wound discharge of the sick person. Exposure can result in the spread of disease only if it happened 7 days before person became ill and up to 1 day after treatment began.
Close contacts include:
Classroom, daycare, workplace and social contacts are not considered close contacts. Antibiotics are given to close contacts. Anyone with close, direct contact with someone with GAS, even if they receive antibiotics, should watch for symptoms. Close contacts should seek medical help immediately if they feel sick within a month after their last contact with the ill person.
Antibiotics - cephalexin, cephadroxil, or cephradine - are given to close contacts. Erythromycin, clarithromycin and clindamycin are given if other drugs cannot be used.