WHAT IS TUBERCULOSIS?

 

TB is caused by a bacterium called Mycobacterium tuberculosis , belonging to the Mycobacteriaceae family consisting of about 200  members. Some of Mycobacteria cause diseases like TB and leprosy in humans and others infect a wide range of animals. In humans , TB most commonly affects the lungs (Pulmonary TB) , but it can also affect other organs (extra pulmonary TB). TB is a very ancient disease and had been documented to have existed in Egypt as early as 3000 BC. TB is a treatable and curable disease.

Transmission: TB is spread from person to person through the air . When people with lung TB cough , sneeze or spit, they propel the TB germs into the air

Symptoms: Common symptoms of active lung TB are cough with sputum and blood at times, chest pains, weakness, weight loss, fever and night sweats.

Global impact of TB ; In 2019 ,87% of new TB cases occurred in the 30 high TB burden countries. Eight countries accounted for two thirds of new TB cases; India, Indonesia, China, Philippines, Pakistan, Nigeria, Bangladesh and South Africa. India reported 1.8 million TB cases between January and December 2020 as compared to 2.4 million the year before. In 2019 , MDR-TB remained a public health crisis and a health security threat .Multi Drug Resistant Tuberculosis (MDR-TB) is a strain of TB that cannot be treated with the most powerful first-line treatment anti TB drugs . Extensively Drug Resistant Tuberculosis (XDR-TB) is a form of  TB caused by bacteria that are resistant to several of the most effective anti-TB drugs.

BCG Vaccine: BCG was developed by two Frenchmen , Albert Calmette and climate Guerin , by modifying a strain of Mycobacterium bovis( that causes TB in cattle). It was first used in humans in 1921. In India BCG was first introduced in a limited scale in 1948 and became a part of the National TB control Programme in 1962. In addition to it's primary use as a vaccine against TB, it protects against respiratory and bacterial infections of the newborns , and other mycobacterial diseases like Leprosy and Buruli's Ulcer. It is also used as an immunotherapy agent in cancer of the urinary bladder and malignant melanoma. One intriguing fact about BCG is that it works well in some geographic locations and not so well in others. Generally , the farther a country is from the equator , the higher is the efficiency. It has a high efficiency in the UK, Norway, Sweden and Denmark; and little or no efficacy in countries on or near the equator like India, Kenya and Malawi , Where the burden of TB is higher.

Global Efforts

The WHO has launched a joint initiative "Find .Treat.All .#EndTB" with the Global Fund and Stop TB Partnership. WHO releases Global TB report.

India's Efforts

National Strategic plan for TB elimination (2017-2025), The Nikshay Ecosystem , Nikshay Poshan Yojana, TB Harega Desh Jeetega Campaign.

VPM ( vaccine Project Management ) 1002 and MIP( Mycobacterium Indicus Pranii) are two vaccines.