Learning About Streptococcal Skin Infections
Streptococcal skin infections are bacterial infections that affect the skin and underlying tissue. They are often caused by Group A streptococcal (strep) bacteria. When the strep bacteria get into open skin (such as from a cut, a scratch, or an insect bite), they can cause an infection. These can be mild infections on the surface of the skin. Or they can be deeper and more severe.
Strep bacteria can also cause other problems. These include strep throat, scarlet fever, streptococcal toxic shock syndrome (STSS), and rheumatic fever.
There are two types of strep bacteria that can cause strep skin infections. Group A strep is the most common cause. Group B is the other cause.
Group A strep (GAS)
- Group A strep can cause a wide range of skin infections. Examples are impetigo, cellulitis, erysipelas, and necrotizing fasciitis. It can also cause infections in the upper respiratory tract.
- It is contagious and can be spread through respiratory droplets. It can also be spread through contact with infected skin, sores, saliva, and nasal discharge.
Group B strep (GBS)
- Group B strep is commonly found in the gastrointestinal and genital tracts. It is usually harmless. But it can cause skin and soft tissue infections.
What are the symptoms?
Symptoms vary depending on the type of strep skin infection. Common symptoms include:
- Fever.
- Chills.
- Warm skin.
- Itchy or painful lesions.
- Rash.
- Skin swelling.
- Skin that is sore or tender to the touch.
- Dark or reddish streaks from the original site.
- Feeling tired.
Many of these symptoms can be caused by other skin conditions. Make sure you see a doctor for a diagnosis.
How are these infections diagnosed?
Your doctor will do an examination and ask questions about your health history and symptoms. The doctor may also do a bacterial culture. This test can help confirm the diagnosis and the type of bacteria present.
How are they treated?
Treatment depends on the type of skin infection you have and how severe it is. You may be given antibiotics. You may need to take these by mouth or apply them to the skin. Or they may be given through an intravenous (I.V.) line. For more serious cases, such as necrotizing fasciitis, you may need surgery to remove damaged tissue.
Current as of: January 19, 2026
