Bacillus Calmette–Guérin

Bacillus Calmette–Guérin (BCG) is a vaccine primarily used against tuberculosis. In countries where tuberculosis or leprosy is common, one dose is recommended in healthy babies as close to the time of birth as possible. In areas where tuberculosis is not common, only children at high risk are typically immunized, while suspected cases of tuberculosis are individually tested for and treated. BCG also has some effectiveness against Buruli ulcer infection and other nontuberculous mycobacteria infections. Additionally, it is sometimes used as part of the treatment of bladder cancer.

History[edit | edit source]

The BCG vaccine was first used in humans in 1921. It was developed by Albert Calmette and Camille Guérin, who named the vaccine by combining their last names. The vaccine was the result of 13 years of research and testing, which began in 1908.

Production and Composition[edit | edit source]

BCG is a live attenuated strain of Mycobacterium bovis, a bacterium closely related to Mycobacterium tuberculosis, which is the causative agent of tuberculosis in humans. The vaccine strain was cultured and attenuated (weakened) at the Pasteur Institute in France.

Efficacy and Use[edit | edit source]

The BCG vaccine is not completely effective in preventing tuberculosis; it primarily prevents severe forms of the disease in children. However, its protective effect appears to diminish over time. Despite this, it remains in use due to its protective effect against severe forms of TB in children and because it is safe, cheap, and easy to administer.

Side Effects[edit | edit source]

Common side effects include fever, pain at the injection site, and swollen glands. Serious side effects are rare and include severe allergic reactions and inflammation of the lungs.