Group A streptococcal (GAS) infections occur when bacteria enter your body and causes an illness. Most illnesses are mild and affect the skin and throat. The GAS bacteria is contagious and spreads easily. Antibiotics treat group A streptococcal infections.
Group A streptococcal (GAS) infections occur when a microorganism (bacteria) enters your body and causes an illness, most often in your skin and throat. There are more than 120 strains of group A Streptococcus bacteria, which is the bacteria that causes group A streptococcal infections.
The majority of illnesses caused by GAS bacteria are mild. Sometimes, GAS infections cause severe, life-threatening symptoms if you don’t receive treatment.
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There are several types of group A streptococcal (GAS) infections that can range from mild infection, like a sore throat, to severe or life-threatening conditions.
Mild illnesses include:
Certain types of group A strep bacteria can cause severe infections including:
Group A streptococcal infections can affect anyone since the bacteria easily spreads from person to person. People who have a GAS infection are contagious while they’re ill. They can pass the bacteria to you by coughing or sneezing or you can get the bacteria if you come into contact with an infected part of their skin (lesion).
An estimated 10 million mild group A streptococcal infections that affect the throat and skin occur every year.
Symptoms range in severity and vary based on the illness that the group A streptococcus bacteria caused. Mild symptoms of group A streptococcal infection include:
Symptoms that affect the skin from a group A streptococcal infection include:
Severe symptoms of a group A streptococcal infection include:
Group A Streptococcus bacteria causes group A streptococcal infections.
Your immune system is responsible for defending your body from outside invaders, like bacteria, that cause illness. When bacteria enter your body, you experience symptoms. At the same time, your immune system works to destroy the bacteria to limit the amount of harm it does to your body.
Sometimes your immune system needs a little bit of help to destroy bacteria that are in your body, which is why your healthcare provider will offer medicine like antibiotics to reduce your symptoms faster.
Yes, group, A Streptococcus bacteria is contagious. The bacteria spread through contact with someone who has a GAS infection including:
The bacteria is most contagious when you experience symptoms of being sick. You can prevent the spread of GAS bacteria by staying home if you’re sick, wearing a mask and treating any wounds you might have.
Diagnosis is dependent on what type of infection you have. First, your provider will check your symptoms and offer a physical exam. They'll ask you questions about your symptoms like how long you’ve had them and how severe they are.
Your provider will offer tests to confirm a diagnosis including:
Antibiotics usually treat group A streptococcal infections. There are two types of antibiotics that your provider will give you to treat your infection depending on what type of infection you have. You might receive a cream that you rub onto your sores (topical) or antibiotics in the form of a pill (oral).
Antibiotics offer several benefits to help you feel better after infection including:
There are no vaccines available to prevent group A streptococcal infections, but vaccines are currently in development.
There are several types of medicines available to treat group A streptococcal infections including:
It could take between three to five days until you start to feel better after taking antibiotics to treat a group A streptococcal infection. Symptoms should reduce after a few days if you have a mild infection. Severe infections could take up to two weeks until you start to feel better.
Even though there is no vaccine to prevent group A streptococcal infections, you can reduce your risk of getting an infection or spreading infection by having good hygiene. Good hygiene includes:
If you have a group A streptococcal infection, you could feel ill for several days until your antibiotics and your immune system target the bacteria in your body. While you’re sick, make sure you stay home and rest until your symptoms reduce to prevent the spread of the bacteria.
If you get a group A streptococcal infection, there is a chance that you could get the infection again in the future if you’re exposed to the bacteria.
While rare, some strains of the group A Streptococcus bacteria from an infection can spread to other parts of your body, which can cause complications including:
Group A streptococcal infections can be dangerous for people who are pregnant and young children. If you are pregnant and experience symptoms or if your child shows symptoms of a group A streptococcal infection, visit your healthcare provider immediately.
Visit your healthcare provider if you have serious symptoms, your infection gets worse or your symptoms don’t go away after two weeks with treatment.
A note from Cleveland Clinic
Group A streptococcal infections cause temporary illnesses that are easily treated with antibiotics. If you experience symptoms, visit your healthcare provider to receive treatment to minimize the amount of time you’ll feel under the weather. Infections can be serious and spread to other parts of your body, so don’t delay getting treatment.
Last reviewed by a Cleveland Clinic medical professional on 05/02/2022.
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