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Streptococcal A pharyngitis or tonsillitis


The majority of sore throats, such as pharyngitis and tonsillitis, are caused by viruses.

However, these infections are sometimes caused by bacteria, specifically Group A Streptococcus β hemolyticus. Streptococcus A is responsible for:

  • 20 to 30% of pharyngitis or tonsillitis in children;
  • 5-15% of pharyngitis or tonsillitis in adults.

Streptococcal A pharyngitis and tonsillitis mainly affect children aged 3 to 15. They occur mainly in winter and spring.


Symptoms of streptococcal A pharyngitis and tonsillitis include:

  • sensitivity of the ganglions in the neck;
  • pain when swallowing;
  • fever;
  • severe sore throat;
  • white spots on the tonsils at the back of the throat;
  • nausea and vomiting;
  • abdominal pain, specifically in children.

It should be noted that these infections are characterized by a sudden onset.


In the case of viral pharyngitis, no antibiotic treatment is necessary. The vast majority of cases heal within 3 to 5 days. Medication to relieve fever or discomfort may be used if necessary.

In the case of streptococcal A pharyngitis or tonsillitis, treatment with antibiotics allows you to:

  • reduce the duration of symptoms by about one day;
  • reduce complications and person-to-person transmission of the infection.

When to consult

An non-emergency consultation is recommended if you develop symptoms following contact with someone infected with streptococcus.

A consultation is also recommended if your symptoms persist for more than 72 hours, even without contact with someone infected with streptococcus.

If your health is at immediate risk, such as difficulty breathing, go to the emergency room.

Talk to a nurse on the phone

For a telephone consultation with a nurse, call 811, option 1.

Last update: November 8, 2023


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