How is tuberculosis caused

The resulting drug-resistant strains are deadlier and more difficult to treat. In countries where tuberculosis is more common, infants often are vaccinated with bacille Calmette-Guerin BCG vaccine. The BCG vaccine isn't recommended for general use in the United States because it isn't very effective in adults. Dozens of new TB vaccines are in various stages of development and testing.

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This content does not have an Arabic version. Overview Tuberculosis TB is a potentially serious infectious disease that mainly affects the lungs. Request an Appointment at Mayo Clinic. Share on: Facebook Twitter. Show references Basic TB facts. Centers for Disease Control and Prevention. Accessed Dec. Jameson JL, et al. In: Harrison's Principles of Internal Medicine. McGraw-Hill; Mayo Clinic; Tintinalli JE, et al.

McGraw Hill; Related Associated Procedures Chest X-rays. CDT Expert Alert: Precision medicine, digital technology hold potential as powerful tools against tuberculosis March 22, , p. Tuberculosis TB. Section Navigation. Facebook Twitter LinkedIn Syndicate. Basic TB Facts. Minus Related Pages. How TB Spreads. TB Risk Factors. Back to Tuberculosis TB.

Tuberculosis TB is caused by a type of bacterium called Mycobacterium tuberculosis. It's spread when a person with active TB disease in their lungs coughs or sneezes and someone else inhales the expelled droplets, which contain TB bacteria. Although TB is spread in a similar way to a cold or flu , it is not as contagious.

You would have to spend prolonged periods several hours in close contact with an infected person to catch the infection yourself.