BCG Vaccine Overview

Tuberculosis , or TB, is a bacterial infection caused by the Mycobacterium tuberculosisbacterium. The bacteria typically infect the lungs, but they can infect other areas of the body, like the kidney, 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 standing nearby. TB is most commonly spread through repeated contact, such as within a family. However, short-term exposure can also cause TB.

Children are at increased risk of getting TB. Because of these risks, preventing TB through vaccination is very important to children’s health in countries where TB is common

At one point, TB was the leading cause of death in the US. As treatments were developed, the rates began to drop. Today, there are many fewer cases.

TB is still a major health problem throughout the world, particularly in Africa. This is largely due to the high number of people with AIDS . They are at a higher risk of getting TB.

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

• A cough that is persistent for three weeks or longer
• Chest pain
• Coughing up blood or phlegm
• Weakness
• Fatigue
• Loss of appetite
• Fever and chills
• Night sweats

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

The Bacille Calmette-Guerin vaccine, or BCG, prevents TB.

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

The following individuals should be considered for vaccination:

• Primarily intended for use in children:

• It is widely given in the developing world.
• In the developed world, it may be given in certain cases. For example, a child may get the vaccine if he is around adults who have TB that cannot be treated with medicines.
• Healthcare workers and people who work in labs—Vaccination is only considered after repeated exposure to patients with TB that is not responding to medicine.

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

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 that are not affected by previous BCG vaccination.

Common side effects of the vaccine include:

• Swollen lymph nodes
• Redness at the injection site
• Fever
• Bloody, frequent, or painful urination
• Abdominal discomfort or vomiting

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

Symptoms of an allergic reaction (eg, rash, trouble breathing) require medical care right away.

You should not get the vaccine if you:

• Have a compromised immune systems, such as those who are infected with HIV/AIDS
• Are undergoing an organ transplant
• Are pregnant

Because TB is airborne, prevention of airborne transmission is important.

Containing the virus 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.

WHERE CAN I GET MORE INFORMATION?

US National Institute of Allergy and Infectious Disease
http://www3.niaid.nih.gov/

US National Library of Medicine
http://www.nlm.nih.gov/

References:

BCG vaccine. Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/tb/pubs/tbfactsheets/bcg.htm . Accessed February 6, 2007.

Kaufmann SH, Hussey G, Lambert PH. New vaccines for tuberculosis. Lancet. 2010 Jun 12;375(9731):2110-9.

Pediatric tuberculosis fact sheet. American Lung Association website. Available at: http://www.lungusa.org/site/pp.asp?c=dvLUK9O0Eb=35778 . Accessed February 6, 2007.

Questions and answers about TB. US Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/nchstp/tb/faqs/qa_introduction.htm#Intro1 . Accessed February 6, 2007.

Rouanet C, Locht C. Boosting BCG to protect against TB. Expert Rev Respir Med. 2010 Jun;4(3):339-48.