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 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.
Complete the medical test information form (PDF)
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