A strep test looks for infection caused by streptococcus bacteria called Group A Streptococcus.
A strep test is done to find out if strep bacteria are causing a sore throat. If your health care provider finds that your child has strep throat, he or she will prescribe antibiotics. Treatment with antibiotics may help your child feel better sooner and reduces the chance of developing more serious problems that can be caused by strep, such as heart problems. Strep is the only common cause of sore throat for which antibiotics are needed.
It is best not to take any antibiotics before a check for strep. Tell the health care provider if your child took antibiotics during the 3 days before the test.
There are two types of strep tests: a throat culture and a rapid antibody test. For both tests your provider gets a sample by rubbing a cotton swab against a tonsil in the back of the throat. The sample is sent to a lab.
Ask your health care provider when and how you will get the result of your child's test.
Usually, a positive strep test result means that your child has strep, and a negative result means that your child does not have strep throat.
Although these tests are very precise, they are not perfect. Cultures are more accurate and reliable than rapid tests. A culture may be done even though a rapid test is negative to make sure your child does not have a strep infection. The strep culture test also provides more information than the rapid strep test. In addition to showing whether your child has strep throat, it may show the specific kind (strain) of strep bacteria. It can help your health care provider know which antibiotic will be most effective in treating the infection. For this reason, your provider may not prescribe an antibiotic until the results of a culture test are back.
If your test result is positive, ask your child's health care provider: