Origins, Indications, Techniques, Administration, Efficacy, and Complications of the Bacillus Calmette-Guérin (BCG) Vaccine

Historical Development and Origins of the BCG Vaccine

The Bacillus Calmette-Guérin (BCG) vaccine was developed in the early 20th century by French bacteriologists Albert Calmette and Camille Guérin. It was introduced as a preventive measure against tuberculosis (TB), one of the deadliest infectious diseases in human history.

Indications for BCG Vaccine Administration

BCG vaccination is primarily used for tuberculosis prevention, especially in regions with high TB prevalence. It is also employed in the treatment of bladder cancer as an immunotherapy agent.

Techniques and Administration

• Intracutaneous injection (most common method)
• Given to neonates and infants shortly after birth in TB-endemic areas
• Used in bladder cancer therapy via intravesical instillation

Efficacy of the BCG Vaccine

The BCG vaccine shows variable effectiveness in preventing pulmonary TB but demonstrates significant efficacy in protecting against severe forms of the disease, such as miliary TB and TB meningitis in children.

Complications and Side Effects

Some common and rare complications include:

• Localized skin reactions
• Swollen lymph nodes
• Disseminated BCG infection in immunocompromised individuals