lungs with tuberculosis with microscopic bacteria



What is TB and how is it spread?
Tuberculosis (TB) is caused by a bacterium called Mycobacterium tuberculosis. The bacteria usually causes infection in the lungs, but TB bacteria can cause infection in any part of the body such as the kidney, spine, and brain. TB is a treatable illness.

TB bacteria spreads through the air from one person to another. Getting TB typically requires many hours of spending time near a person who is sick from TB. TB cannot be spread by touching doorknobs, tables, utensils or other surfaces.

What are the symptoms of a person sick with TB (also called TB disease or active TB)?
Some common symptoms of active TB include:

  • A cough lasting more than three weeks
  • Fever
  • Heavy sweating at night
  • Loss of appetite
  • Unintended weight loss
  • Coughing up blood
  • Pain in the chest
  • Chills
  • Weakness or fatigue 

What is the difference between TB infection and TB disease?
People with latent TB infection have TB bacteria in their bodies but they are not sick and cannot spread the bacteria to others. However, they may develop TB disease in the future. They are often prescribed antibiotics to prevent them from developing TB disease.

People with TB disease are sick from TB bacteria. They usually have symptoms of TB disease. People with TB disease of the lungs or throat can spread the bacteria to others. They are prescribed drugs that can treat TB disease.

How is TB diagnosed?
TB infection is typically diagnosed by a skin or blood test. Results are available in one to three days. Most people who are infected will not be sick and cannot give TB to others. If a person is sick with symptoms due to TB, a chest X-ray is required, regardless of the blood test results.


Frequently Asked Questions & Answers about TB
Basic TB Facts (link to CDC)
Exposure to TB Information
(link to CDC)