Throat Culture: About This Test
What is it?
A throat culture is a test to find a bacterial or fungal infection in the throat. Instead of a regular throat culture, you may get a different type of test (called a molecular test) that looks for DNA (the genetic information inside cells). A molecular test checks for the most common type of bacteria that causes a throat infection.
Both types of tests are done by swabbing the back of your throat
Why is this test done?
A throat culture may be done to:
- Find the cause of a sore throat. Most sore throat infections are caused by a virus. A throat culture shows the difference between a bacterial infection and a viral infection. This can help guide treatment.
- Check a person who may not have any symptoms of infection but who carries bacteria that can spread to others. This person is called a carrier.
How do you prepare for the test?
- In general, there's nothing you have to do before this test, unless your doctor tells you to.
- Tell your doctor if you have recently taken any antibiotics.
How is the test done?
- You will be asked to tilt your head back and open your mouth as wide as you can.
- Your doctor will press your tongue down with a flat stick (tongue depressor) and then examine your mouth and throat.
- A clean cotton swab will be rubbed over the back of your throat, around your tonsils, and over any red areas or sores to collect a sample.
- The sample may also be collected using a throat washout. For this test, you will gargle a small amount of salt water and then spit the fluid into a clean cup. This method gives a larger sample than a throat swab. It may make the culture more reliable.
How long does the test take?
The test will take less than a minute.
What happens after the test?
Throat culture test results for bacterial infections are ready in 1 to 2 days, depending on which bacteria are being tested for. Test results for a fungus may take about 7 days.
Rapid strep test
Another type of test is called a rapid strep test. You can’t get this test through an Alberta Health Services lab or service. You may be able to buy this test at your local pharmacy.
You’ll get the results of a rapid strep test within 10 to 15 minutes. If you get a negative test result, it could mean that you don't have a bacterial throat infection. But sometimes the results of these tests are wrong.
If your symptoms don't go away, make an appointment to see your healthcare provider. They may want to send you for a throat culture or a molecular test to check for a throat infection.
When should you call for help?
Call your doctor or nurse advice line now or seek immediate medical care if:
- You have a new or higher fever
- You have a fever with a stiff neck or severe headache.
- You have new or worse trouble swallowing.
- Your sore throat gets much worse on one side.
Watch closely for changes in your health, and be sure to contact your doctor or nurse advice line if:
- You do not start to feel better after 2 days (48 hours).
- You do not get better as expected.
Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to keep a list of the medicines you take. Ask your doctor when you can expect to have your test results.
Where can you learn more?
Go to https://www.healthwise.net/patientEd
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Adaptation Date: 2/25/2022
Adapted By: Alberta Health Services
Adaptation Reviewed By: Alberta Health Services
