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Strep Throat

What is strep throat?

Strep throat is an infection caused by Group A streptococcus (group A strep) bacteria. Strep throat is a common type of sore throat in children, but it's not very common in adults.

What are the symptoms?

Common symptoms of strep throat include a sore and red throat but most sore throats are not caused by strep. Additionally, people may experience:
  • Severe pain when swallowing
  • Fever of 101ºF degrees or above
  • Swollen lymph nodes in the front of the neck
  • Headache
  • Abdominal pain
  • Vomiting
  • Nausea.
How is strep throat spread?

Strep throat spreads through direct person to person contact. Typically, a person is infected when they come into contact with droplets from an infected person's cough or sneeze. It takes 2-5 days after initial exposure for symptoms to appear.  People with strep throat are generally most infectious when they are sick (have symptoms). People are still able to spread the infection for 24 hours or longer after starting treatment. People with strep throat should stay home from work, school, or daycare until they no longer have a fever and until 24 hours after starting treatment.

Who gets strep throat?

Anyone can get strep throat but it is most common among 5-15 year olds. It is rare in children younger than 3 years of age. The most common risk factor is close contact with another person with strep throat.

How is strep throat diagnosed?

A medical test by your healthcare provider is needed. Most sore throats are not caused by strep.

How is strep throat treated?

People with strep throat should be treated with antibiotics. When left untreated, the symptoms are usually self-limited. However, in some cases, complications can occur if left untreated. Also, treatment reduces the likelihood of spreading the infection to people around you. Keep in mind that not all sore throats will need to be treated with antibiotics.

How can I prevent strep throat?

Handwashing, especially after coughing and sneezing and before preparing or eating foods helps stop the spread of infections. Additionally, people with strep throat should stay home from work, school, or daycare until they have taken antibiotics for at least 24 hours. Antibiotics taken for strep throat reduce the length of time people are sick and help prevent the spread of infection to friends and family members.

Boston Public Health Commission
1010 Massachusetts Ave, 6th Floor, Boston, MA 02118.
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