Group A Streptococcus

(Streptococcus pyogenes)

Group A Streptococcus (GAS) or Streptococcus pyogenes is a bacterium that can be found in the throat or on the skin of healthy individuals. While the majority of illness caused by GAS is relatively mild, usually presenting as “strep throat” or impetigo (a skin infection), GAS may also cause more serious and sometimes deadly infection.  

Although rare, severe invasive GAS disease can occur when bacteria break through a person’s defenses and enter parts of the body, such as the blood or muscle, where it is not usually found. Two of the most severe, but least common, forms of invasive GAS disease are necrotizing fasciitis and streptococcal toxic shock syndrome (STSS). Necrotizing fasciitis (NF), often called “flesh-eating bacteria” by the media, occurs when the bacteria release toxins that destroy muscles, fat, and skin tissue. With STSS, the release of toxins can cause a rapid drop in blood pressure and subsequent organ failure. Of note, STSS is not related to “toxic shock syndrome” which is associated with tampon use and is caused by a toxin-producing strain of Staphylococcus aureus.
 
GAS infections are treated with a course of antibiotics. In severe cases, patients may need to stay in the intensive care unit to adequately monitor and treat the infection.  For patients diagnosed with NF, early and aggressive surgery is usually required to remove the damaged tissue and to prevent the spread of the disease. 

GAS spreads through direct contact with the nasal and oral secretions of those who are infected or exposure to the bacteria through open wounds or sores. The spread of all types of GAS infection can be reduced by good hand washing, especially after coughing, sneezing, and before food preparation and consumption.

For more information, please visit the CDC GAS Disease website.

Image courtesy of the CDC Public Health Image Library

Maryland Emerging Infections Program/ABCs
Johns Hopkins University Bloomberg School of Public Health
Candler Building
111 Market Place, Suite 850, Room 8546
Baltimore, MD 21202
Phone: 410-223-1810
Fax:  410-223-1815
Email: mdabcs@jhsph.edu