Group A Streptococcus
Group A Streptococcus (GAS), also known as Streptococcus pyogenes, is a bacterium often found in the throat and on the skin. People may carry GAS in the throat or on the skin and have no symptoms or illness. Most GAS infections are relatively mild illnesses, like "strep throat" or impetigo (a skin infection). A small proportion of people may get a serious or life-threatening infection with GAS.
Frequently Asked Questions about GAS:
How common is GAS?
Millions of people in the United States get mild GAS infections, such as "strep throat", every year. CDC estimates about 11,000 to 13,000 cases of invasive GAS occur each year, and between 1,100 and 1,600 people die from these more serious GAS infections.
In Alaska, health care providers are only required to report invasive GAS infections, so we don't know how many cases of mild infection there are. On average, there are 60-90 cases of invasive GAS in Alaska each year.
What are emm types?
emm types are different molecular subtypes of GAS. There are over 200 emm types. Some types are more common than others, and some are associated with certainkinds of disease. However, they are all still GAS.
How are Group A Streptococci spread?
People who are actively sick with GAS, like those who have strep throat or anopen skin infection, are more likely to spread GAS to others than people who carry the bacteria but are not sick. Because GAS can cause several different kinds of infections, it can be spread in several different ways.
People who carry GAS in their throat can spread it by coughing or sneezing, which creates small droplets. When other people breathe in these droplets, or touch an item with droplets on it and then touch their mouth or nose, the bacteria can be transferred to a new person. It is possible for People who carry GAS in their throat can spread it by coughing or sneezing, which creates small droplets. When other people breathe in these droplets, or touch an item with droplets on it and then touch their mouth or nose, the bacteria can be transferred to a new person. It is possible for GAS to spread by drinking from the same glass or sharing utensils if a person has GAS in their throat.
People with skin infections, or who carry GAS on their skin, can spread the bacteria by direct contact.
How can I protect myself from GAS?
Frequent handwashing is important in preventing the spread of GAS. Wash your hands, or use hand sanitizer, after you sneeze or cough, and before and after preparing food or eating. Encourage those around you to do the same.
People with sore throats should be seen by a doctor, who can perform a test to see if the illness is caused by streptococci. People diagnosed with strep throat, or other GAS infections, should stay home from work, school, or daycare until 24 hours after starting antibiotics.
All wounds should be kept clean, and watched for signs of infection. An infected wound may look red, swollen, and feel warm on the skin around the wound, and may ooze or have drainage. If a wound seems infected, immediately seek medical care.
It is not necessary for everyone exposed to someone with a GAS infection to take antibiotics. However, in some situations, your doctor may recommend antibiotics. This decision should be made after talking to your doctor.
What kinds of diseases are caused by GAS?
Most infections caused by GAS are not serious. These include "strep throat" and impetigo, a kind of skin infection.
Rarely, GAS can cause serious infections, which is sometimes called "invasive Group A Strep." Some important kinds of serious GAS include sepsis, necrotizing fasciitis, and streptococcal toxic shock syndrome.
Sepsis is a condition where bacteria infect the blood, and cause a strong immune response that makes people very sick. Sepsis can be caused by many kinds of bacteria, including GAS.
Necrotizing fasciitis is a condition where bacteria rapidly destroy the muscles and fat below the skin. It can be caused by many bacteria, including GAS. Necrotizing fasciitis often starts as a skin infection or cellulitis.
Streptococcal toxic shock syndrome (STSS) is a condition where blood pressure drops rapidly as a result of the body's reaction to toxins released by GAS bacteria. The loss of blood pressure can cause organ failure.
Who is at risk for serious GAS disease?
Few people who come in contact with GAS will develop invasive disease. Serious GAS disease most often occurs in:
- People with chronic illnesses, such as cancer, diabetes, and chronic heart or lung disease
- The elderly and newborns
- People who have a history of alcohol abuse
- People who have a history of injection drug abuse
- Have skin wounds or lesions, such as those with cuts, chicken pox, or surgical wounds
- People with other immune-compromising conditions
What are early signs of a serious GAS infection?
Early signs and symptoms of sepsis include:
- Fever, chills, or feeling very cold
- Extreme pain or discomfort
- Clammy or sweaty skin
- Confusion or disorientation
- Short of breath
- High heart rate
Early signs and symptoms of necrotizing fasciitis include:
- Redness at the wound site, especially if the redness gets much larger over several days
- Skin changes from red to purple, or starts to peel
- Blisters on the skin
- Fever
Early signs and symptoms of STSS include:
- Sudden onset of general or localized severe pain
- Dizziness or confusion
- Flu-like symptoms: fever, chills, nausea, vomiting, and aches
- A flat red rash over large areas of the body (less common)
How is GAS treated?
Many antibiotics can be used to treat GAS. Your doctor will choose which ones are best for the kind of infection you have. For necrotizing fasciitis, sometimes surgery is necessary to remove infected tissue.
