Strep throat

How is strep throat diagnosed in children?

If a strep throat infection is suspected a rapid strep test or a throat culture is necessary to confirm the diagnosis.

Rapid strep test

• During a rapid strep test, the doctor rubs a cotton swab in the back of the mouth and over both tonsils to collect a sample of bacteria from the infected area. This can be done in the doctor’s office.

• Within a few minutes, the test determines whether group A Streptococcus bacteria are present in the child’s throat.

• Although generally reliable, rapid strep tests are not always 100 percent accurate. They can sometimes produce a “false negative” and show no sign of bacterial infection when strep is actually there.

Throat culture

• If the rapid test comes back negative but the child shows signs of strep, the sample may be sent to the lab for a throat culture.  A throat culture may also be done instead of a rapid strep test.

• A throat culture means that the cotton swab sample will be put on a special plate that allows group A Streptococcus bacteria to grow. If bacteria do not grow, the child does not have group A Streptococcus in the throat

Carriers of strep throat

Group A Streptococcus can live in the nose and throat of some people without causing an infection. These people are called carriers. It’s not always easy to know who is a carrier; doctors usually make this diagnosis on a case-by-case basis.