Invasive Group A Streptococcus Fact Sheet

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Group A Streptococcus are a group of bacteria

Group A Streptococcus (GAS) are usually found on the skin and in the nose and throat.  People can have these bacteria and not feel sick.  GAS may cause a mild infection like Strep throat or impetigo (infection of the skin).  These bacteria can also cause more severe 'invasive' infections like meningitis (infection of the lining of the brain and spinal cord), endocarditis (infection of the heart), or osteomyelitis (infection of the bone).  Two very serious diseases caused by GAS are necrotizing fasciitis and streptococcal toxic shock syndrome.

Necrotizing fascilitis is a very serious infection

Necrotizing fascilitis is a rare infection in fatty tissues and muscles of the body that can be caused by many bacteria, including Group A Streptococcus.  I usually begins with an infection of the skin (cellulitis), but sometimes only a small bruise or insect bite can lead to necrotizing fascilitis.

Signs and symptoms of necrotizing fascilitis to look for include:

  • Fever
  • Skin wound or redness on skin that gets much larger in just 1 to 3 days
  • Skin changes from red to a dark purple color, skin starts to peel
  • Blisters of fluid that form on skin
  • Skin and muscles that become very painful and swollen


Streptococcal toxic shock syndrome (STSS) is also a very serious infection

STSS happens in people who have a GAS infection that is so severe that their internal organs stop working.  It is different from the toxic shock syndrome related to tampon use.

Signs and symptoms of STSS to look for include:

  • Fever
  • Severe pain in the part of the body with the GAS infection
  • Headache and vomiting
  • Muscle aches
  • Confusion
  • Red rash all over the body
  • Breathing problems
  • Shock (feeling lightheaded and having a very fast pulse)


The following persons are at higher risk for necrotizing fascilitis and STSS:

  • People with long-lasting illnesses like cancer, diabetes, and kidney disease
  • Newborns and the elderly
  • People who have just had surgery or an injury
  • Alcoholics
  • People with active chickenpox


Necrotizing fascilitis and STSS both require immediate medical attention

It is important to contact your doctor immediately if you think you or anyone you live with may have either of these infections.  They will not get better on their own, but can be treated with the quick use of antibiotics.  Early treatment may reduce the risk of deah