What is group A streptococcus?

Group A streptococcus is a type of bacteria. It is also sometimes known as:

• GAS
• strep A
• streptococcus pyogenes

Healthy people can be carriers of group A streptococcus without having any symptoms or becoming unwell. The bacteria can be found in the throat and on the skin.

What is group A streptococcal infection?

Group A streptococcus can cause infections in some people, making them unwell. Group A streptococcal infections can cause:

• sore throat, also known as strep throat
• tonsillitis
• scarlet fever

Group A streptococcal infections can also cause skin infections, such as impetigo, cellulitis and erysipelas. Erysipelas is an infection of the outer layer of skin and can usually be treated at a general practice or urgent care clinic with antibiotics.

Invasive group A streptococcal (iGAS) infections

In rare cases, the bacteria can cause a severe, life-threatening infection known as invasive group A streptococcal (iGAS) infection. This includes bone and joint infections such as osteomyelitis and septic arthritis. Other types of invasive group A streptococcal infection include:

• blood infection (bacteraemia)
• pneumonia
• meningitis
• sepsis
• necrotising fasciitis (sometimes called 'flesh-eating bacteria' — a life-threatening infection)
• toxic shock syndrome

People with invasive group A streptococcal infections need treatment in hospital.

What are the symptoms of group A streptococcal infection?

One common symptom of group A streptococcal infection is fever. Other symptoms of group A streptococcal infection depend on where the infection is in your body.

Early symptoms of invasive group A streptococcal infections can include fever and:

• nausea and vomiting
• shortness of breath
• headache
• severe muscle aches
• redness and swelling at the site of a skin wound
• skin rash

What causes group A streptococcal infection?

Group A streptococcal infection is spread through droplets and skin-to-skin contact. If you are in close contact with someone with group A streptococcal bacteria, you may become infected if you:

• breathe in droplets from their coughs or sneezes
• touch something with droplets on it and then touch your mouth or nose
• touch them or have contact with infected skin sores
• kiss them

Anyone can get a group A streptococcal infection, but people who are most at risk are:

• children under 5 years of age, especially newborn babies
• people who are pregnant or have recently given birth
• older people
• people who live with someone who has a group A streptococcal infection
• people with poor access to hygiene facilities
• people who live or spend time in crowded conditions
• people with weak immune systems or chronic illnesses (such as diabetes or heart disease)

Children are more likely to become infected with group A streptococcus than adults. They also generally spend more time in crowded environments, such as schools, and play in close physical contact.

When should I see my doctor?

Visit your doctor if you have a severe sore throat, skin sores or a wound that is not getting better.

When to seek urgent care

If you think you or someone you care for has a group A streptococcal infection, it is important to see a doctor as soon as possible.

The infection can spread through the body and can become serious if not promptly treated with antibiotics.

A person with invasive group A streptococcal infection can become very sick within 12 to 24 hours, so it's important to seek medical care promptly.

How is group A streptococcal infection diagnosed?

Your doctor will ask about your symptoms and do a physical examination.

Depending on your symptoms and the type of infection you have, your doctor will recommend tests to check if you have a group A streptococcal infection. These may include a:

• swab of your throat or a skin sore
• blood test
• sample of another body fluid

Invasive group A streptococcal infection is a nationally notifiable disease. This means that your doctor must tell the Department of Health if you're diagnosed. The Department needs to track all cases of invasive group A streptococcal infection to help find outbreaks and improve healthcare responses.

How is a group A streptococcal infection treated?

Group A streptococcal infection is mainly treated with antibiotics. People with invasive group A streptococcal infection need treatment in hospital. In some cases, you may need surgery.

Self-care

In general, it can help to drink plenty of fluids and rest when you have symptoms such as a sore throat or skin infections.

Medicines

Group A streptococcal infections are treated with antibiotics.

Your doctor will work out which antibiotic is best, depending on where your infection is located and how serious it is.

Your health practitioner may also suggest pain-relief medicines such as paracetamol or ibuprofen to help with symptoms such as sore throat.

Antibiotics for close contacts of people with invasive group A streptococcal infection

Talk to your doctor if you have been in close contact with someone with an invasive group A streptococcal infection.

Your doctor may recommend you take a course of antibiotics to reduce your risk of infection.

What are the complications of group A streptococcal disease?

In some people, a group A streptococcal infection can lead to serious complications. These can include:

• Rheumatic fever, which can affect your heart, joints, brain and skin.
• Post-streptococcal glomerulonephritis (which affects your kidneys).
• Severe scarring or limb loss from necrotising fasciitis or toxic shock syndrome.

Can group A streptococcal infection be prevented?

You can help prevent group A streptococcal infections with good hygiene. Make sure to wash your hands often, especially after sneezing or coughing and before preparing, serving or eating food.

Keep surfaces clean, including bathroom sinks, taps and door handles. Wash clothes and bedlinen regularly to protect all members of your household.

If you or your child has strep throat or another form of group A streptococcal infection, you should stay home from pre-school, school or work for at least 24 hours after starting antibiotic treatment.

Resources and support

Call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with you 24 hours a day, 7 days a week.

If you are pregnant or have a child and are concerned about group A streptococcal infection, call Pregnancy, Birth and Baby on 1800 882 436 for advice, support and guidance from maternal child health nurses.

Languages other than English

Sydney Children's Health Network has a factsheet on invasive group A streptococcus available in several community languages.

The Victorian government has posters on hand hygiene available in many community languages.

Information for Aboriginal and/or Torres Strait Islander peoples

Perth Children's Hospital has a range of fact sheets as part of the Keeping Our Mob Healthy initiative.

Watch the No Germs on Me video on hand washing.

Find an Aboriginal Community Controlled Health Organisation (ACCHO) or Affiliate near you.