Tuberculosis (TB) is caused by a bacterium called Mycobacterium tuberculosis. The bacteria usually attack the lungs, but TB bacteria can attack any part of the body such as the kidney, spine, and brain. Not everyone infected with TB bacteria becomes sick.
Some people develop TB disease soon after becoming infected (within weeks) before their immune system can fight the TB germs. Other people have latent TB infection and may get sick years later, when their immune system becomes weak for another reason. Treating latent TB infection is effective in preventing TB disease.
Tuberculosis Fact Sheet
Learn more about symptoms, transmission, testing, and treatment.
Symptoms
General symptoms may include feeling weak or sick, weight loss, fever, and/or night sweats. Symptoms of TB of the lungs may include cough, chest pain, and/or coughing up blood. TB can also affect other parts of the body, such as the brain, kidneys, or spine. Other symptoms depend on the part of the body that is affected. TB disease in the lungs may cause symptoms such as:
- Cough that lasts three weeks or longer
- Pain in the chest
- Coughing up blood or sputum (phlegm from deep inside the lungs)
Other symptoms of TB disease are weakness or fatigue, weight loss, no appetite, chills, fever, and sweating at night. People who have latent TB infection do not feel sick, do not have any symptoms, and cannot spread TB to others.
Frequently Asked Questions
How does someone get TB?
TB is spread from person to person through the air. The bacteria are passed into the air when a person with TB disease coughs or sneezes. People can breathe in these bacteria and become infected.
How do I know if I have TB?
Symptoms of TB disease: Cough, night sweats, and weight loss usually lasting longer than 2-3 weeks. Some individuals with active disease will have minimal or no symptoms.
Tuberculin skin testing or TST: A small amount of test solution is injected into the skin to determine exposure. This skin test site is checked between 48-72 hours later for a positive reaction known as “induration.” The induration is measured to determine if it is a positive or negative test.
Interferon Gamma Ray Assay or IGRA: A blood test that can be done to determine exposure. The test usually results in 3-4 days.
Chest X-ray: Used to check for active disease in the lungs.
Sputum collection: A sample of secretions produced by a cough can be sent to the laboratory for analysis.
What is Latent TB?
Latent TB Infection is when a person has been infected and has the potential to develop TB disease, but is not currently ill.
TB disease is when a person has been infected and damage is occurring as a result of TB infection that has overwhelmed the body’s defenses which can make the individual ill.
Is there treatment for TB?
Both TB infection and TB disease are treated with specific medications.
Who is most at risk for TB?
- Persons with recent exposure to an active TB case
- Small children and the elderly
- Persons with HIV/AIDS
- Diabetics
- Persons who take medications that affect their immune system, such as steroids or chemotherapy agents
- Persons with certain cancers
- Persons who have a weak immune systems due to substance abuse