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Streptococcal Infections

(Strep Infections)


The Manual's Editorial Staff

Last full review/revision Aug 2021| Content last modified Aug 2021
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What are streptococcal (strep) infections?

Streptococcus (simply called strep) is a common group of bacteria. Different types of strep cause different diseases. Most often they cause sore throat Sore Throat Sore throat is pain in the back of the throat. The pain can be severe and is usually worsened by swallowing. Many people with sore throat refuse to eat or drink. Sometimes pain is also felt... read more 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 strep 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 strep infections?

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

What are the complications of strep 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 strep infection?

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

How do doctors treat strep infections?

Doctors treat strep 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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Bacterial Infections: Gram-Positive Bacteria
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