Strep A Test
Reviewed
A strep A test checks for group A Streptococcus bacteria, which cause strep throat and other infections. There are two types: a rapid strep test (results in 10–20 minutes) and a throat culture (results in 24–48 hours). The test helps determine if a sore throat is due to strep (bacterial) or a viral infection, guiding appropriate treatment with antibiotics to prevent complications like rheumatic fever.
Preparation and collection
No special preparations needed.
Understanding this test
Use the reference interval and units printed by the laboratory that performed the test. A result outside that interval is not a diagnosis by itself, and a result inside it does not rule out every condition. Your symptoms, history, medicines, timing, and related tests can change what the result means.
- A rapid strep test can sometimes miss an infection that a throat culture would find.
- Some people carry group A strep without symptoms (carriers) and usually do not need antibiotics.
- Having strep throat does not protect you from getting it again in the future.
What to do next
If diagnosed with strep throat, take antibiotics as prescribed for the full course (usually 10 days). Stay home until fever-free and after at least 12–24 hours of antibiotics. Wash hands often, cover coughs and sneezes, and clean frequently touched surfaces to prevent spread.