Tuberculosis (TB) caused by the bacterium Mycobacterium tuberculosis, is one of the oldest diseases known to humankind. The bacteria usually attack the lungs, but TB bacteria can attack any part of the body such as the kidney, spine, and brain. If not treated properly, TB disease can be fatal. It continues to claim about 1.3 million lives each year and is second only to COVID-19 as the greatest killer worldwide due to a single infectious agent. An estimated 10.6 million people fall ill with tuberculosis every year, including 5.8 million men, 3.5 million women and 1.3 million children.
Over 80 percent of TB cases and deaths occur in low- and middle-income countries. 70% of new cases occur in Bangladesh, China, Democratic Republic of the Congo, India, Indonesia, Nigeria, Pakistan and the Philippines.
Eradication of TB will require the development and incorporation of new and more effective vaccines that can replace the current neonatal BCG vaccine, which offers partial protection for infants and young children from severe forms of TB but does not protect adolescents and adults, who account for a majority of the TB transmission. There are currently a number of vaccine candidate in clinical trials, including those to prevent TB disease, TB infection and to help improve the outcomes of treatment for TB disease.
Standard anti-TB drugs have been used for decades, and resistance to the medicines is widespread. Multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant TB (XDR-TB) are forms of TB caused by bacteria that do not respond to the most powerful, first-line anti-TB drugs. The treatment options for MDR and XDR-TB are limited, recommended medicines are not always available; the long therapy (up to two years of treatment) is more costly and can produce severe adverse drug reactions in patients. Vaccines would offer the best chance to contain the accelerating spread of MDR-TB.