What is Group A Streptococcal Disease (GAS)?
- Group A streptococci (GAS) are germs commonly found in the throat and on the skin that can cause a wide range of infections.
- GAS infections are often mild illnesses such as strep throat (strep throat is a bacterial infection that can make your throat feel sore and scratchy) and skin or wound infections.
- Rarely, these germs can cause serious, even life-threatening diseases if they move to areas outside the throat and skin. Then they are called invasive GAS (iGAS). Two of the most severe forms of iGAS are streptococcal toxic shock syndrome and necrotizing fasciitis also known as the flesh-eating disease.
- People may be at a higher risk of developing invasive disease if they have underlying health conditions, a recent viral infection, use substances or have breaks in their skin.
How is GAS spread?
GAS germs can be spread by being in close contact with someone who is sick with GAS. The GAS germs can spread:
- when a sick person coughs or sneezes
- through contact with the open wounds/lesions
- through sharing needles/drug equipment
- through open-mouth kissing or providing mouth to mouth resuscitation to a sick person
- sharing cigarettes, straws, cups, bottles, utensils or anything else with saliva on it
What are the symptoms of GAS?
People may carry the germs in their throat or on the skin and have no symptoms of illness. Symptoms usually start one to three days after contact with the germs, but it may take longer for symptoms to appear, depending on the site and type of GAS infection.
- GAS of the throat includes symptoms of fever, sore throat, tender neck glands, swollen tonsils. Ear infections may also develop.
- GAS of the blood includes symptoms of fever, chills, headache, generally unwell feeling, rapid breathing, and increased heart rate.
- STSS includes symptoms of fever, sudden drop in blood pressure, and possible organ failure.
- Flesh-eating disease includes symptoms of fever, chills, fatigue, vomiting, and diarrhea. It can cause rapid severe pain, redness and swelling around a wound, and destruction of muscles, fat, and skin tissue.
How is GAS treated?
- GAS can be treated with antibiotics. Severe infections may require hospital care.
- Individuals with severe skin infections may require surgery to remove damaged tissue and stop the infection from spreading.
How is GAS prevented?
- Cover coughs and sneezes.
- Wash hands often-especially before and after injecting, touching wounds or cuts, after coughing or sneezing, and before preparing or eating food.
- Keep wounds clean and covered. Watch for signs of infection such as redness, swelling, pain, or drainage, and seek medical care if these appear.
- Do not share anything that my have saliva on them.
- Never reuse, share, lend, or borrow any drug injecting or smoking equipment.
- Clean and disinfect surfaces and objects frequently.
- Stay up to date with vaccinations.
- Stay home when you are sick.
Where can I get more information about GAS?
Contact the Communicable Disease Control (CDC) Program at 705-474-1400, or toll-free at 1-800-563-2808, ext. 5229 or email us at cdc@healthunit.ca.
References:
- Government of Canada. (2024). Group A streptococcal diseases (Streptococcus pyogenes).
- Heymann, David L, (2022). Control of Communicable Disease Manual. 21st ed., pp. 604-621. Washington, DC.
- Ministry of Health. (2024). Infectious Diseases Protocol, Appendix 1, Case Definitions and Case Specific Information, Disease: Group A Streptococcal Disease, invasive (iGAS).
Created: Apr 2026, by CDC