Symptoms and Signs of Group A Strep (GAS) Infection

Medical Author:
Medically Reviewed on 8/13/2021

Doctor's Notes on Group A Strep (GAS) Infection

Group A strep (GAS), also called Streptococcus pyogenes or group A beta-hemolytic Streptococcus, is a gram-positive coccus (spherical bacteria) that is abundant, highly contagious, and spread primarily through person-to-person (skin-to-skin) contact and via respiratory droplets, as the human skin and mucous membranes are the only known reservoir for GAS. Upper respiratory tract (pharyngitis) infections and skin infections (cellulitis) with GAS are among the most common bacterial infections

Symptoms of group A strep (GAS) tonsillopharyngitis include: 

Symptoms of group A strep (GAS) skin diseases such as impetigo, erysipelas, and necrotizing fasciitis include:

  • impetigo: blistering or infected lesion, the destruction or irritation of which results in the development of a coating described as honey crusting. 
  • erysipelas: skin redness, hardening, tenderness, a raised, sharply demarcated border, and a consistency often compared to that of an orange peel. 
  • necrotizing fasciitis: marked tissue destruction in the deep fascial layers of the skin, fever and severe pain.

What Is the Treatment for Group A Strep Infection?

Antibiotics are the treatment for invasive GAS infections as well as noninvasive group A strep infections. Although many different types of antibiotics may be adequate, it is best to determine antibiotic sensitivity of GAS bacteria in each individual case to make sure the bacteria are susceptible to the selected antibiotics.

Minor GAS infections such as strep throat or skin infections are usually treated with oral antibiotics. For severe infections, hospitalization and administration of intravenous (IV) antibiotics may be required.

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Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.