Strep throat

Strep throat is a bacterial infection. In some cases it can lead to rheumatic fever, resulting in permanent heart damage. Read about the symptoms and treatment.
Clinically reviewed by:
Dr Mataroria Lyndon on 23.7.2021


  • Strep throat is a contagious bacterial infection which causes a sore throat.
  • It’s diagnosed with a throat swab.
  • For most people, strep throat will go away on its own, but some people will require antibiotics.
  • If strep throat is left untreated in some people, it can progress into rheumatic fever, which can permanently damage a person’s heart.
  • Strep throat can lead to rheumatic fever in more high-risk groups if left untreated. It mainly affects Māori and Pacific children and young people (aged 4 to 19 years), especially if they have other family members who have had rheumatic fever. They should see a doctor or nurse if they show ANY sign of sore throat
  • A sore throat can also be one of the symptoms of COVID-19. If you develop a cough, sore throat, runny nose, feel short of breath or experience a loss of smell, you need a COVID test. You can also call the dedicated COVID-19 Healthline on 0800 358 5453 for further advice.  
  • Most other sore throats are caused by viral infections, which can’t be treated with antibiotics and just have to run their course.

Unlike a viral sore throat, strep throat isn’t any more prevalent at certain times of year.

Need help?

What causes the strep throat?

  • Strep throat is caused by Streptococcus bacteria.
  • It’s spread by infected people coughing and sneezing around others, who then inhale airborne droplets.
  • It can also be spread by kissing, sharing food or drinks – essentially anything where saliva is exchanged.


  • A sore throat 
  • Trouble swallowing
  • Redness at the back of your mouth
  • Fever
  • Smelly breath
  • Swollen glands around the neck
  • Enlarged tonsils
  • A white coating on the tonsils 
  • Headache
  • Tummy pain
  • Nausea and/or vomiting
  • Sometimes a patient may also get a skin rash in conjunction with a fever – this is known as scarlet fever. While anybody can catch it, it’s more common in children.

Strep infection can be diagnosed by doing a throat swab.


  • The treatment of strep throat depends on your risk of getting rheumatic fever. If you are at low risk, treatment is aimed at self-care to ease the pain and the infection will get better on its own in a few days. However, some people will also need antibiotic medicine.
  • Antibiotics are used to treat people who are at risk of developing rheumatic fever or at more risk of spreading strep throat. It’s very important that if you or your child are prescribed antibiotics, you finish the course – even if you start to feel better earlier.
  • For everyone else, strep throat should improve without the need of any medication.
  • Pain can be managed with medicated throat lozenges, gargles or sprays, however none of these should be given to children.
  • Penicillin and amoxicillin are both antibiotics that are used to treat strep throat. Usually these will be prescribed as a 10 day course of capsules or liquid.
  • A one-off antibiotic injection may also be offered to people who have trouble taking pills or holding down liquid medicine.
Common over-the-counter medications
  • Paracetamol can help with pain and fever. Be sure to follow the dosage instructions as these will be different for children and adults.
Home remedies
  • Sucking on a teaspoon of honey can help to relieve a sore throat, although this shouldn’t be given to any kids under the age of 12 months.
  • Gargling salt water can also help to relieve a sore throat. The recommended ratio is 1 tsp of salt to 1 cup of warm water.
  • Warm water with fresh lemon juice and honey mixed into it can also be soothing.
Proactive protection
  • Don’t kiss, share food or drinks with people who have a sore throat, or have been diagnosed with strep throat until their symptoms have cleared.
  • Wash your hands thoroughly before eating or preparing food.
  • Create some space between anyone who is sharing a room to minimise germs being spread through coughing and sneezing.

Should I see a doctor?

  • For people at higher risk of rheumatic fever, it is very important that a sore throat is always checked early by a nurse or GP. This is because untreated strep throat can cause rheumatic fever and heart damage for life.

You are at higher risk of rheumatic fever if:

  • you have had rheumatic fever before
  • someone in your family or household has had rheumatic fever.

Or if you have 2 or more of the following:

  • Māori or Pasifika ethnicity
  • Aged 3–35 years
  • Live in poorer or crowded living conditions.
  • If you belong to any of the groups that are more at risk of developing rheumatic fever, see a doctor if you have any strep throat symptoms.
  • Children are particularly at risk of developing rheumatic fever. It’s difficult to tell the difference between strep throat and a viral sore throat, so if your child has any symptoms, get them seen by a doctor quickly.
  • See a doctor immediately if your child appears to be dehydrated or is having trouble breathing properly.

How long does strep throat last?

Most people will recover from strep throat in a few days.