The world of healthcare is currently spotlighting the Bacille Calmette-Guérin (BCG) vaccine in celebration of its 100th year of existence. As of now, the BCG vaccine stands as the only preventive measure against Tuberculosis (TB).
About Tuberculosis
Tuberculosis is caused by Mycobacterium tuberculosis, which belongs to the larger Mycobacteriaceae family that houses about 200 members. Some of these microorganisms are responsible for human diseases such as TB and Leprosy, while others tend to infect animals. Primarily, humans experience TB in their lungs (pulmonary TB), though it can also invade other organs, leading to extra-pulmonary TB. The disease has a long history, tracing its roots back to 3000 BC in Egypt. Now, fortunately, TB is both treatable and curable.
Transmission of TB
The bacterium gets transferred from one person to another through the air. When individuals with lung TB cough, sneeze, or spit, they launch the TB germs into the surrounding atmosphere.
Symptoms of TB
Active lung TB presents itself in symptoms, which can include coughing with occasional blood-containing sputum, chest pains, weakness, weight loss, fever, and night sweats.
The Global Impact of TB
In 2019, a shocking 87% of new TB cases were reported in the 30 high TB burden countries. Major contributors to this figure are India, Indonesia, China, Philippines, Pakistan, Nigeria, Bangladesh, and South Africa, which collectively accounted for two-thirds of the new TB cases. Between January and December 2020, India reported 1.8 million TB cases, a decrease from the 2.4 million cases documented in the previous year.
The threat of MultiDrug Resistant Tuberculosis (MDR-TB) and Extensively Drug Resistant Tuberculosis (XDR-TB) also looms large. These TB strains show resistance to several potent anti-TB drugs and hence pose both a public health crisis and a health security threat.
The BCG Vaccine
Developed by Albert Calmette and Camille Guerin, the BCG vaccine was first administered to humans back in 1921. The vaccine was introduced on a limited scale in India in 1948 before it was included in the National TB Control Programme in 1962. Besides its primary purpose as a TB vaccine, it has applications spanning from protection against newborn respiratory and bacterial infections to treatment for mycobacterial diseases such as Leprosy and Buruli’s ulcer.
Interestingly, the efficacy of the BCG vaccine varies across different geographical locations. Countries farther from the equator, such as the UK, Norway, Sweden, and Denmark, report higher efficiency while those near or at the equator, including India, Kenya, and Malawi, experience lower efficacy despite having a higher TB burden.
Related Initiatives: Global and India’s Efforts
On a global scale, WHO, the Global Fund, and Stop TB Partnership have launched an initiative titled Find. Treat. All. #EndTB. WHO also periodically releases the Global Tuberculosis Report.
India has strategized with the National Strategic Plan (NSP) for Tuberculosis Elimination (2017-2025), The Nikshay Ecosystem (National TB information system), Nikshay Poshan Yojana (NPY-financial support), and the TB Harega Desh Jeetega Campaign. Currently, two vaccines, VPM (Vaccine Projekt Management) 1002 and MIP (Mycobacterium Indicus Pranii), have been developed to fight against TB and are undergoing phase-3 clinical trials.
