[Answered] Discuss the historical and clinical evidence that suggests the role of social determinants, such as poverty and living conditions, in the incidence and mortality of TB. How has the focus shifted from these determinants to biomedical interventions over the years?

Tuberculosis (TB) is an infectious airborne bacterial disease caused by Mycobacterium tuberculosis, which most commonly affects the lungs but can also damage other parts of the body. According to WHO’s 2018 Global TB Report, India accounted for 27% of the total new TB infections in 2017, the highest in the world. The role of social determinants, including poverty and living conditions, in the incidence and mortality of TB is well-established and has been a major focus of research and public health efforts.

What role do social determinants play in the incidence and mortality of TB?

• Poverty: A majority of TB patients in India are affected due to undernourishment. Poverty impacts their accessibility to food and their ability to get treated. It is still a big problem in India associated with problems of undernourishment and poor and unhygienic living conditions.
• Overcrowding: The rapid spread of TB is facilitated by the overcrowding found in slums and other informal settlements, which are frequent in areas of extreme poverty. The danger of transmission is increased by inadequate ventilation and close contact.
• Malnutrition: Inadequate nutrition is frequently caused by poverty. A person’s immune system becomes weakened by malnutrition, making them more prone to contracting TB infection and less equipped to fight it off once infected. Various studies like RATIONS published in the Lancet journal now show that food supplementation is not just an effective treatment for people with TB, but is also an effective vaccine for their family members.

How has this focus shifted from social determinants to medical intervention in recent years?

• Improved diagnostic methods: Biomedical research has led to improved diagnostic tools, such as rapid molecular tests, and the development of drug regimens like Directly Observed Treatment, and Short-Course (DOTS) which are more accurate and quick diagnostic options and have improved treatment outcomes. Telemedicine and mobile health applications have improved access to healthcare services, bridging the gap for those in remote or underserved areas.
• Drug-resistant TB: The emergence of drug-resistant TB strains has heightened the urgency of finding effective treatments. The use of oral medications has reduced the duration of DR-TB treatment from 24 months to 6 months which is a big improvement in medical science.
• Global Health Initiatives: The global health community, including organizations like WHO, has emphasized the importance of biomedical interventions with increased funding and support to developing nations. For eg, WHO suggests the use of oral BPaLM/BPaL (Pretomanid (Pa) bedaquiline (B), linezolid (L), and sometimes moxifloxacin (M)) regimen for DR-TB patients which is found to be effective at curing 89-91 per cent of multidrug-resistant TB (MDR-TB).

Conclusion:

Nikshay Poshan Yojana launched by the Government of India in 2018 to offer food supplementation or cash transfers to buy food is a step in the right direction for TB patients. The need is to expand the coverage of this benefit to all household members of the patient to improve the chances of achieving the ambitious target of eradicating TB by 2025.