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BCG Vaccine

(Tuberculosis Vaccine)

What Is Tuberculosis?

Tuberculosis, or TB, is a bacterial infection that typically targets the lungs. TB can also infect other areas of the body such as the kidneys, spine, or brain.

TB is spread from the lungs of a person with TB through coughing. When a person coughs or sneezes, the bacteria travel into the air and may be inhaled by a person who is nearby. TB is most commonly spread through repeated contact such as within a family. Short-term exposure can also cause TB.

At one point, TB was the leading cause of death in the US. As treatments were developed, TB rates began to drop. Today, there are far fewer cases, but the disease is still present.

TB is still a major health problem throughout the world, particularly in Africa. People with HIV infection also have a higher risk of getting TB.

Symptoms depend on where the bacteria have settled and grown in the body. The lungs are often infected. Symptoms of TB infection in the lungs include:

TB can usually be treated successfully with antibiotics. Without treatment, the disease can be fatal.

What Is the BCG vaccine?

The Bacille Calmette-Guerin vaccine, or BCG, can help prevent TB. However, this vaccine does not always protect people from getting TB.

The vaccine contains live, weakened bacteria. It is given as shot in the arm.

Who Should Get Vaccinated and When?

The following individuals should be considered for vaccination:

The vaccine is usually given one time. It may be given twice in some cases.

What Are the Risks Associated With BCG Vaccine?

The vaccine may cause a TB skin test to have a false-positive reading. This means that you may test positive for TB even though you do not have it. Blood tests are available to check for TB infection in people that are not affected by previous BCG vaccination.

Common side effects of the vaccine include:

More serious side effects may rarely occur and could lead to serious illness or death.

Symptoms of an allergic reaction require medical care right away.

Who Should Not Get Vaccinated?

You should not get the vaccine if you:

What Happens in the Event of an Outbreak?

Containing TB depends on giving antibiotics and isolating people who are infected. It is important to take all of the antibiotics to eliminate the bacteria and to avoid spreading it to others.


Centers for Disease Control and Prevention

The BCG World Atlas on BCG Policies


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Kaufmann SH, Hussey G, Lambert PH. New vaccines for tuberculosis. Lancet. 2010;375(9731):2110-2119.

Pulmonary tuberculosis. EBSCO DynaMed Plus website. Available at: Updated November 1, 2017. Accessed December 7, 2017.

Tuberculosis (TB). American Lung Association website. Available at: Accessed December 7, 2017.

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Tuberculosis (TB) vaccine. Centers for Disease Control and Prevention website. Available at: Updated May 13, 2009. Accessed December 7, 2017.

Last reviewed November 2018 by EBSCO Medical Review Board David L. Horn, MD, FACP  Last Updated: 12/20/2014