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Tuberculosis (TB)

Last Updated: October 1, 2021
HealthLinkBC File Number: 51a
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What is TB?

TB is a serious disease caused by a germ (bacteria) that spreads through the air.

TB usually affects the lungs, but can also affect other parts of the body like glands, bones, joints, kidneys, the brain and reproductive organs.

You can cure TB. In B.C., medicines to prevent TB, or to cure TB, are free through Provincial TB Services and public health units. In B.C., we do not provide the bacille Calmette-Guerin (BCG) vaccine and it is not routinely available in Canada.

How does TB spread?

TB spreads from person to person through the air when someone who is sick with TB in the lungs coughs, sneezes, sings or talks. If you breathe in the air containing the TB bacteria, you can become infected. Usually, you need a significant amount of close, regular contact with a person who is sick with TB in the lungs to develop TB infection. Not everyone infected with TB bacteria will get sick with TB disease.

What is the difference between TB infection and TB disease?

TB infection occurs when you breathe TB bacteria into your lungs and your body's defences stop the bacteria from growing and making you sick. A person infected with TB will not feel sick and cannot spread TB bacteria to others. This is also called “sleeping TB” or latent TB infection (LTBI).

TB disease occurs when you breathe TB bacteria into your lungs and the bacteria start to grow in number, and they may spread throughout your body. You may or may not feel sick, as how you feel depends on where the TB bacteria are growing. When you have growing TB disease in the lungs you might spread TB bacteria to those around you. We call it active TB disease.

What are the chances of a TB infection becoming TB disease?

If you are a healthy person and have latent TB infection, you have a 5 to 10% chance of developing active TB disease over your lifetime. However, if an illness or strong medications weaken your immune system, there is a higher risk you can develop active TB disease. For example, people with human immunodeficiency virus (HIV) infection and TB infection are at very high risk for active TB disease. Those with diabetes and TB infection are at moderate risk.

What are the symptoms of TB disease?

Symptoms of active TB disease of the lungs include cough (dry or wet) for 2 weeks or longer, sputum, chest pain and shortness of breath. Sputum is mucous or phlegm that you cough up from deep inside your lungs. You may also have unexplained weight loss, fever, night sweats, loss of appetite and tiredness or fatigue. If TB has affected other parts of your body, the symptoms may vary.

How can I be tested for TB?

Visit your health care provider for a check-up if you have symptoms of TB disease or want to know if you have LTBI. Your health care provider will do a TB assessment and order the appropriate tests. There may be a cost depending on the reason for your TB test(s).

Your health care provider uses a tuberculin skin test or TB skin test to look for TB infection. The test tells you if your body has “seen” the TB bacteria before. It does not tell whether the TB bacteria are latent or active. For more information about TB skin testing, see Healthfile #51d Tuberculosis Skin Test.

The TB skin test results, your reason for testing and your general health may mean you need further TB testing. Further testing could include a TB blood test, chest x-ray or sputum.

A chest x-ray and sputum are usually used to test for active TB disease. A chest x-ray is a picture of your lungs that your health care provider examines to see if TB bacteria are growing in your lungs. Your health care provider sends the sputum (mucous or phlegm from deep in the lungs) to a lab to test for TB bacteria. For more information, see HealthLinkBC File #51b Sputum Collection for Tuberculosis (TB) Testing.

Where can I get tested?

You may be able to get testing done at your local public health unit, your health care provider’s office, a travel health clinic, and Island Health TB Program and Provincial TB Services clinics in Vancouver and New Westminster.

To find your local public health unit, visit the ImmunizeBC Find a Clinic locator at www.immunizebc.ca/finder.

To find TB testing locations near you, visit the HealthLinkBC FIND Services and Resources Directory at www.healthlinkbc.ca/services-and-resources/find-services.

What is the treatment?

You can treat both LTBI and active TB diseases. All pills for TB treatment are free and available through Provincial TB Services and public health units. Your health care provider will monitor you closely while you take the medication.

Latent TB Infection treatment: Treatment of LTBI helps prevent the “sleeping” TB bacteria from “waking up” and making you sick. The LTBI medicines are recommended for those people most likely to get active TB.

Speak with your health care provider if you want to take LTBI medications. It is important that they make sure you don’t have active TB disease before starting LTBI medications. It is also important to understand the medication side effects of each pill and to know when you need to call your health care provider.

Active TB Disease treatment: Treatment of active TB disease cures you and prevents spreading TB to other people. A combination of pills is used for 6 months or longer. It is important to take all the pills you received, as directed. TB treatment takes a long time because the TB bacteria are strong and hard to get rid of. It is also important to understand the medication side effects of each pill and to know when you need to call your health care provider.

During your treatment for active TB, you will visit your health care provider regularly. They will ask you to provide chest x-rays and sputum to check that you are responding to treatment. Your health care provider will let you know when your treatment is complete.

To help protect other people, it is important to tell your health care provider who you have been in contact with to help identify people at risk for TB infection. All information you give will be kept confidential.

How can I reduce the risk of giving TB to other people?

If you have contagious active TB disease in the lungs or throat, you can spread the TB bacteria to other people, even after weeks of treatment. Your health care provider will ask you to wear a mask and stay at home to decrease the risk of spreading the disease. This is called home isolation; it is a very important step you must do to protect other people. Your health care provider will tell you when you can stop home isolation.

For more information, see HealthLinkBC File #51c Home Isolation for Tuberculosis (TB).