Discuss the global burden of TB-HIV under various parameters and the importance of the dual pandemic. Mention the major countries where both epidemics are considered to be important.

Give an outline of DR-TB situation in India. Give Incidence and prevalence, why India should bother, and where does India stand in Global scenario as far as DR-TB is concerned?

Discuss the global burden of DR-TB under various parameters and historical trend.

TB is one of the top burdensome infectious diseases in India. It is estimated that, around 1/4th (26%) of the world's TB cases are in India, translating to about 30 Lakhs new TB cases emerging each year (TB incidence). Against this estimated incidence the National TB Elimination program reported around 19 lakh new and relapse cases in the year 2021.

• Globally, an estimated 11 million people fell ill with TB (incidence) in 2021.
• Historically, it has been the top infectious disease killer. In 2021, there were an estimated 1.4 million TB deaths and an additional 187 000 deaths among HIV-positive people.
• Three countries accounted for 42% of global cases in 2021: India (26%), the Russian Federation (8.5%) and Pakistan (7.9%).

Pathogenesis of TB is a product of interaction between bacterial activity and immune responses in the host.

Generally, in a person with good cellular immunity, the clearance of Mycobacterium tuberculosis (Mtb) is quite good and the chances of developing the active disease are less.

Ventilation is an important determinant of airborne infections. Poor ventilation at a patient's residence or at a healthcare facility, will result in more risk attached for any airborne infections.

Poor Ventilation and Inadequate Air Circulation as Risk Factors for Tuberculosis (TB)

Discuss how poor or waning immune response increases risk of TB infection and disease. Mention common conditions with poor host immunity.