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Tuberculosis FACT SHEETS

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Active TB disease

What is active TB disease?

Tuberculosis (TB) disease is caused by germs (bacteria) that are spread through the air from person to person. TB germs get into the air when someone with active, infectious TB disease coughs, sneezes, sings, plays a wind instrument or to a lesser degree, talks. These germs can stay in the air for hours. If you breathe in the TB germs, your body’s immune (defence) system may kill the TB germs. If your body’s defence system doesn’t kill the TB germs, they can remain alive but inactive in your body – this is called latent TB infection. If TB germs become active (multiply and grow in the body), this is called active TB disease. If you have active TB disease, you will feel sick and may infect other people.

What are the symptoms of active TB disease?

TB is a serious disease that attacks the lungs and sometimes spreads to other parts of the body (this is called active TB disease outside the lungs). You may have symptoms in the parts of your body where the TB germs are growing.

A person with active TB disease:

  • May have an abnormal chest x-ray or positive sputum smear (or culture)
  • Has active TB germs in his/her body
  • Usually feels sick and may have symptoms such as coughing, fever, and weight loss
  • May spread TB germs to others
  • Needs to take drugs to treat active TB disease

If you have active TB disease in the lungs, you may have the following symptoms:

  • a bad cough that lasts longer than three weeks
  • pain in the chest
  • coughing up blood or sputum (phlegm)
  • weakness or feeling very tired
  • weight loss
  • lack of appetite
  • chills
  • fever
  • night sweats

How do I know if I have active TB disease?

If you feel sick, see your doctor. Your doctor will examine you and order tests, such as a chest x-ray. If you are coughing, your sputum (phlegm) may contain TB germs. If you have active TB disease, you need treatment of to kill the TB germs in your body. Persons with active TB disease of the lungs and airways are considered infectious and may spread TB germs to others.Without treatment, you could die.

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