Bacillus Calmette-Guérin (BCG) vaccine

The Bacillus Calmette-Guérin (BCG) vaccine is a vaccine primarily used to prevent tuberculosis (TB), a serious infectious disease. Developed in the early 20th century, it contains a weakened strain of the bacterium that causes TB. The vaccine stimulates the immune system, preparing it to fight off TB if exposed later. While BCG is effective in preventing severe forms of TB in children, its success in adults is variable. It's commonly given in countries with high TB rates and is also sometimes used as a treatment for bladder cancer.