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Learning About Tuberculosis (TB)

The lungs

What is tuberculosis (TB)?

Tuberculosis (TB) is a serious disease caused by a type of bacteria that is spread through the air. TB is easily spread from person to person through coughs or sneezes. It usually occurs in the lungs, but it can spread to other parts of the body.

What is latent TB?

Latent TB means that you have bacteria in your body that could cause active TB, but your body's defences (immune system) are keeping it from turning into active TB. You don't have any symptoms, so you don't feel sick. And you can't spread it to others. While this means that you don't have active TB, you can develop the disease at some point if you don't have treatment.

What is active TB?

You get active TB (TB disease) when the bacteria that cause the disease overcome your body's defences. Some people get active TB right away. Others may develop it later if the immune system gets weak. When you have active TB, you can spread the disease to others.

What are the symptoms of active TB?

People with active TB may:

  • Cough.
  • Lose their appetite and lose weight.
  • Have night sweats.
  • Have a fever.
  • Have chills.
  • Feel tired and weak.

How is it diagnosed?

Latent TB

You may have a skin or blood test to find out if you have latent TB. Skin tests are used most often.

For a skin test, a small needle places testing material under your skin. In a few days, you will go back to your testing place to be checked for a skin reaction.

For a blood test, your blood is taken and tested.

Active TB

You will start with a skin or blood test. If that test shows that you have been exposed to TB, you will have an X-ray of your chest. The X-ray will show if there is damage to your lungs. And you may be asked to cough up some mucus that is tested in a lab. This test shows if TB is in your lungs. If it is, you can spread it to others by coughing or even just breathing out.

How is it treated?

Latent TB

If you have latent TB, you may be treated with one or more antibiotics for 3 to 9 months. A health professional may watch you take your medicine. This is called directly observed therapy (DOT). DOT is done to help make sure that you don't miss a dose and that all the bacteria are killed.

Active TB

The first phase of treatment for active TB lasts 2 months. During this phase, you take several medicines. The second phase of treatment can last 4 to 7 months or longer. During this phase, the number of medicines you take may be reduced. Treatment for TB takes a long time because the bacteria die very slowly. You will likely start to feel better after a few weeks of treatment. But don't stop your treatment until your doctor says all of the TB bacteria are dead.

A health professional may watch you take your medicine to make sure that you don't miss a dose. Missing doses or stopping medicine too soon can make you sick again. Then you may have to start treatment over again. And the infection can be harder to treat if you have to start over.

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 call line if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

Where can you learn more?

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