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Streptococcal Infections

(Strep Infections)


The Manual's Editorial Staff

Last full review/revision Oct 2019| Content last modified Oct 2019
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What are streptococcal infections?

Streptococcus (simply called strep) is a common group of bacteria. Different types of strep cause different diseases. Most often they cause sore throat (strep throat) or skin infections. But they can cause life-threatening infections in other parts of your body.

  • Streptococcus bacteria can live in and on your body without causing symptoms

  • Infection can happen in your throat, middle ear, sinuses, lungs, skin, tissue under your skin, heart valves, and blood

  • Infections can cause red and painful swollen tissues, scabby sores, sore throat, and a rash

  • Doctors treat streptococcal infections with antibiotics

What causes streptococcal infections?

Streptococcus bacteria can spread from person to person by:

  • Breathing in infected droplets from someone’s sneeze or cough

  • Touching an infected sore

  • Giving birth, where it can spread from mother to baby

What are the symptoms of streptococcal infections?

You have different symptoms depending on where you have the infection:

  • Throat infection (strep throat): Sore throat, swollen lumps in your neck, fever, pus on your tonsils

  • Skin infection: A painful red area on your skin (cellulitis), or yellow, crusty sores (impetigo)

  • Infection under your skin (necrotizing fasciitis): Chills, fever, and severe pain and tenderness in the part of your body that’s infected

Necrotizing fasciitis is very serious. You could get gangrene and lose an arm or leg or even die.

What are the complications of streptococcal infections?

Rheumatic fever gives you painful, swollen joints. Children with rheumatic fever may have uncontrollable, jerky movements of their arms and legs. Rheumatic fever sometimes damages the heart's valves. But heart valve damage usually doesn't show up for many years.

Scarlet fever gives you a rash on your face, then the rest of your body. The rash feels like sandpaper. When it fades, your skin peels. Your tongue gets red bumps, so it looks like a strawberry (called strawberry tongue).

How can doctors tell if I have a streptococcal infection?

Doctors will test a swab from your sore throat or other infected tissue.

How do doctors treat streptococcal infections?

Doctors treat streptococcal infections with antibiotics. For necrotizing fasciitis, you'll be admitted to the hospital and have surgery to take out the dead, infected tissue.

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