Rapid Strep Test for Strep Throat

Exam Overview

For a rapid strep test, the throat and tonsils are swabbed to collect bacteria from the infected area for testing. The bacteria are analyzed to see whether Group A strep (streptococcal) bacteria are causing the sore throat.

A good sample of throat secretions is needed to make sure the test is accurate. A person must remain very still during the procedure so that the doctor is able to collect enough secretions for an accurate test.

Results of a rapid strep test are available in 10 to 15 minutes.

Why It Is Done

A rapid strep test may be done in the following cases:

  • A person has symptoms of strep throat infection.
  • A person has been exposed to strep during an epidemic of rheumatic fever.
  • The person has a personal or family history of rheumatic fever or other serious infections (such as toxic shock syndrome) and has been exposed to strep. In these cases, if there are no symptoms, a culture may be done first because it is more accurate than a rapid strep test.

In general, it is not necessary to test people who have been exposed to strep throat but do not have any symptoms.

Results

Findings of a rapid strep test may include the following.

Normal

A normal or negative test means that strep bacteria may not be present.

  • Sometimes, negative results are wrong. This means that you may have a negative rapid strep test result and still have strep throat.
  • A throat culture may be done if the rapid strep test result is negative.

Abnormal

An abnormal or positive strep test means that strep bacteria are present.

  • Antibiotic treatment can be started.
  • A positive test result does not distinguish those people with an active strep infection from those who are carriers of strep bacteria but actually have a viral infection (rather than a bacterial one).

What To Think About

The rapid strep test costs less than a throat culture and may diagnose strep throat quickly.

Credits

ByHealthwise Staff
Primary Medical Reviewer Kathleen Romito, MD - Family Medicine
Donald R. Mintz, MD, FRCSC - Otolaryngology

Current as ofMarch 28, 2018