There are a wide variety of reasons why you may need to have TB screening. Visit your health care provider for a check-up if you have symptoms of TB disease or want to know if you have latent TB infection. Your health care provider will ask health questions and order any needed tests.
Reasons for TB screening include:
- you have signs or symptoms of active TB
- you were in contact with someone who has TB in their lungs that can spread from person to person
- you work or volunteer in health care
- you have health conditions such as HIV infection, cancer, chronic kidney disease, or diabetes
- you have a low or weakened immune system from immunosuppressive medications
- you are living in a communal setting such as a shelter, corrections, or a treatment program
The testing for TB may be available at BC health units, travel health clinics, BCCDC TB clinics and some doctor's offices.
For many people testing is free, but it depends on why you need the test. Tests for work, school or volunteering usually cost money. There are different types of tests that look for TB. The type of test is chosen based on your health history and sometimes a body (physical) exam.
The TB skin test involves 2 clinic visits, 48 to 72 hours apart.
The tuberculin skin test shows whether or not you have the TB bacteria in your body. It is the most common test used for TB. The test cannot tell the difference between latent or active TB. At the first visit, a health care provider will inject a small amount of fluid (called tuberculin) into the lower part of your arm. At the second appointment, a health care provider will read your body's reaction to the fluid.
- A negative TB skin test usually means that you do not have TB in your body. Most people do not need further testing.
- A positive TB skin test means you might have TB in
your body. Before a diagnosis can be made, more testing is needed.
A TB skin test is used to test for TB infection. In some cases, an IGRA TB blood test may offer more information. The test cannot tell the difference between latent or active TB. You may be offered an IGRA TB blood test if you are at risk of developing active TB disease. Your doctor or nurse will decide if you need this test.
- A negative TB blood test usually means that you do not have TB in your body. Most people do not need further testing.
- A positive TB blood test means you might have TB in your body. Before a diagnosis can be made, more testing is needed.
A chest x-ray may be offered to some people. A chest x-ray is a picture of your lungs. It is often used after you have had a positive TB skin or blood test to see if TB has affected your lungs. If there are changes it's more likely you may have active TB disease.
Sputum tests may be offered to some people. Sputum tests look at the mucus from your lungs. It can help figure out if you have active TB disease and how likely you are to pass TB another person. Learn more by reading the HealthlinkBC file: Sputum collection for TB testing. The healthfile is in English and 7 other languages.
The way you get your TB test results will depend on the type of test that you had. If you had a TB skin test your health care provider will explain results are the second appointment and let you know if you require more testing. For other types of TB tests, the results may take several weeks. When you get tested ask your health care provider how you will get your results and when they will be ready. It is important to follow-up on your results.
Any information shared with your health care provider is confidential, including test results. When you go for TB testing you may be asked to provide personal information. This is used to give the best health care, order tests, and contact you with results. If you are concerned about confidentiality talk to your health care provider.