In News:

In a significant move reinforcing its "Neighbourhood First" policy and commitment to humanitarian aid, India dispatched 13 tonnes of Bacille Calmette-Guerin (BCG) vaccines to Afghanistan. This consignment, delivered to the Afghan Ministry of Public Health in Kabul, aims to bolster the country's national child immunization program against Tuberculosis (TB), particularly in the wake of recent natural disasters and a strained healthcare infrastructure.

I. Understanding the BCG Vaccine

• Nature: The BCG vaccine is a live attenuated vaccine derived from a weakened strain of Mycobacterium bovis (a bacterium that causes TB in cows but is related to the human strain).
• Historical Context: Developed by French bacteriologists Albert Calmette and Camille Guérin, it was first administered to humans in 1921.
• Clinical Utility:
  • Primary Use: It remains the only widely available vaccine against Tuberculosis.
  • Off-label Uses: It offers cross-protection against other non-tuberculous mycobacterial infections such as Leprosy and Buruli ulcer.
  • Immunotherapy: It is used as a standard treatment for superficial bladder cancer (carcinoma).
• Administration & Storage:
  • Method: Administered intradermally (into the skin).
  • Storage: Requires a strict cold chain between 2°C and 8°C.
  • Composition: Supplied as a two-part kit—a freeze-dried vaccine (in amber glass ampoules to protect from light) and a diluent (colorless ampoules) for reconstitution.

II. Tuberculosis (TB): The Global and Regional Burden

TB continues to be a major public health challenge, especially in developing and conflict-affected nations.

• Pathogen: Caused by Mycobacterium tuberculosis, which primarily targets the lungs (pulmonary TB) but can affect other organs (extra-pulmonary TB).
• Transmission: An airborne disease spread through respiratory droplets (coughing, sneezing, or spitting).
• Symptoms: Persistent cough (often with blood), weight loss, night sweats, high fever, and fatigue.
• Vulnerability in Afghanistan: Coverage for BCG vaccination among one-year-olds in Afghanistan has historically hovered around 68%, leaving thousands of children susceptible to severe forms of the disease like miliary TB and TB meningitis.