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  Tuberculosis (TB)

Doctor examining a chest x-ray 

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Communicable Diseases, Emergency Preparedness and Response

Tuberculosis (TB) is caused by bacteria called Mycobacterium tuberculosis complex. It is spread from person to person through the air. People with TB in the lungs and airways (pulmonary and laryngeal TB) can spread the bacteria to others by coughing, sneezing, singing or talking. The likelihood that TB will spread depends on how infectious the person with TB is, the immune system of the exposed person, contact between them (e.g., how often, close or long), and environmental conditions (e.g., ventilation). Exposure to TB can result in latent TB infection or active TB disease.

Latent TB infection: People with latent TB infection have no signs or symptoms and cannot spread TB to others. Although most people with latent TB infection will never become sick due to TB, some may develop active TB because their immune system cannot stop the bacteria from growing. People with latent TB infection who are at higher risk for active TB include: babies and young children, the elderly, and people with weakened immune systems (e.g., due to conditions like HIV or medications). Antibiotics can help prevent those with latent TB infection from developing active TB disease.

Active TB disease:  People with active TB disease are generally sick. Symptoms of TB in the lungs and airways can include: cough lasting two weeks or more, fever, chills, and night sweats. More severe disease can cause chest pain, unexplained weight loss, fatigue or coughing up blood. TB can also occur in other body parts such as the lymph nodes, bones or kidneys. Unlike TB in the lungs and airways, TB in other parts of the body does not spread from person to person. Combinations of antibiotics are used to treat active TB disease.

TB is preventable, treatable and curable with antibiotics.

Page last reviewed:
Page last updated: 2018-10-30 1:22 PM
Uncontrolled print copy. Valid only on day of Print: [date]
Page updated on [date/time] 2018-10-30 1:22 PM
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