[6th June 2026] The Hindu OpED: India needs innovative stratergies to eliminate TB

PYQ Relevance[UPSC 2022] What is the basic principle behind vaccine development? How do vaccines work? What approaches were adopted by the Indian vaccine manufacturers to produce COVID-19 vaccines?Linkage: The PYQ tests understanding of vaccine science, indigenous vaccine development, and the role of biotechnology in addressing public health challenges. The PreVenTB Trial evaluates indigenous vaccines (VPM1002 and Immuvac) for TB prevention, highlighting India’s growing capabilities in vaccine research and the use of biotechnology to combat infectious diseases.

Mentor’s Comment

India’s fight against tuberculosis (TB) has received a major boost with the publication of the ICMR-led PreVenTB Trial. The trial found that the indigenous vaccine candidates VPM1002 and Immuvac provide protection against both pulmonary TB and the difficult-to-diagnose extrapulmonary TB (EPTB). The findings are significant as they offer new evidence from a large real-world Indian population at a time when India continues to bear one of the world’s highest TB burdens. They also strengthen hopes for achieving TB elimination, even as TB remains the leading infectious disease killer globally. 

Why has a “one-size-fits-all” vaccine approach failed in TB control?

1. Diverse Disease Pathways: TB infection can remain latent for years, progress to subclinical disease, or develop into active pulmonary or extrapulmonary TB.
2. Biological Complexity: Individuals differ in infection status, age, comorbidities, and immune responses.
3. Vaccine Limitations: Previous TB vaccine development largely focused on preventing pulmonary TB.
4. Unrealistic Expectations: Search for a single vaccine capable of preventing all forms of TB has repeatedly disappointed global TB control efforts.

How severe is the TB burden and why does it demand urgent action?

1. Global Mortality: TB continues to kill more people annually than any other infectious disease.
2. Burden in LMICs: Incidence in many low- and middle-income countries remains between 200-300 cases per 100,000 population.
3. Elimination Threshold: TB incidence must decline to 10-20 cases per 100,000 population to approach elimination.
4. Indian Context: India carries one of the world’s highest TB burdens, requiring sustained public health investments.
5. Long-Term Challenge: Elimination demands decades of coordinated interventions rather than a single technological solution.

What are the key pillars of a layered TB elimination strategy?

1. Better Detection
   1. Advanced Diagnostics: Enables identification of subclinical TB before progression to active disease.
   2. Risk-Based Screening: Supports early detection among vulnerable populations.
   3. Public Health Impact: Reduces transmission and disease progression.
2. Preventive Therapy
   1. Latent TB Treatment: Prevents inactive infection from progressing to active disease.
   2. Targeted Intervention: Particularly relevant for household contacts and high-risk populations.
3. Vaccination
   1. Critical Tool: Complements diagnostics and preventive therapy.
   2. Population Protection: Reduces progression from infection to disease.
   3. Integrated Strategy: Most effective when combined with nutrition and case management.

What are the major findings of the PreVenTB Trial?

1. Institution: Conducted by the Indian Council of Medical Research (ICMR).
2. Scale: Conducted at multiple sites across India.
3. Participants: More than 12,700 household contacts of TB patients.
4. Target Group: Individuals aged six years and above, including those with comorbidities and varying infection status.
5. Vaccines Evaluated: VPM1002 and Immuvac.
   1. Efficacy of VPM1002
      1. Extrapulmonary TB Protection: 50.4% efficacy against EPTB.
      2. Pulmonary TB Protection: 21.4% efficacy against pulmonary TB overall.
   2. Efficacy of Immuvac
      1. Overall Protection: 64.6% efficacy against all forms of TB.
      2. Children Protection: More than 60% efficacy among children aged 6–10 years.
      3. Progression Prevention: More than 60% efficacy against progression to disease among individuals with latent infection.

Significance

1. First-of-Its-Kind Evidence: Demonstrates efficacy against both pulmonary and extrapulmonary TB.
2. Real-World Conditions: Large Phase III trial conducted in an Indian population.
3. Broad Coverage: Includes multiple age groups and disease forms.

Why is extrapulmonary TB an important policy concern?

Extrapulmonary tuberculosis (TB) is an active Mycobacterium tuberculosis infection occurring in organs other than the lungs. It accounts for 15% to 40% of all TB cases and primarily affects lymph nodes, pleura, the spine, and the central nervous system.

1. Hidden Burden: Harder to diagnose than pulmonary TB.
2. Missed Cases: Frequently underreported and undetected.
3. Higher Morbidity: Associated with severe complications and mortality.
4. Clinical Impact: A reduction of over 50% in EPTB cases would significantly lower patient suffering and healthcare costs.
5. Novel Evidence: Current findings provide rare vaccine efficacy data against EPTB.

What opportunities do the findings create for children and adolescents?

1. Strong Signal: Vaccine efficacy exceeded 60% among school-age children and adolescents.
2. Policy Gap: India currently lacks a structured TB vaccination strategy beyond infancy.
3. Booster Potential: Findings may support future booster-dose vaccination programmes.
4. Disease Prevention: Offers protection before transition to adulthood, when disease burden increases.

Why is nutrition emerging as a critical component of TB control?

1. Low BMI Impact: Reduced vaccine efficacy observed among individuals with low Body Mass Index.
2. Immune Function: Nutritional status influences vaccine effectiveness and disease resistance.
3. Integrated Approach: Vaccination must be aligned with nutritional interventions.
4. Policy Relevance: Supports strengthening nutrition-TB convergence programmes.

What operational advantages does VPM1002 offer?

1. Single-Dose Vaccine: Simplifies deployment.
2. Modified BCG Platform: Uses an established vaccine platform.
3. Manufacturing Ease: Can be produced at scale.
4. Cost Effectiveness: Suitable for large population programmes.
5. LMIC Relevance: Practical for resource-constrained settings.

What lessons can India draw from previous vaccine decisions?

1. TrueNat Example: Indigenous molecular test adopted by the National TB Elimination Programme before WHO qualification.
2. COVID-19 Response: Covaxin received approval under a “clinical trial mode” during the pandemic to accelerate access while evidence accumulated.
3. Rotavirus Vaccine: Indigenous vaccines were introduced despite early uncertainty and later demonstrated significant reductions in severe disease and child mortality.
4. Policy Lesson: Timely deployment based on credible evidence can yield substantial public health gains.

What should India’s future TB strategy look like?

1. Targeted Vaccination: Deployment of VPM1002 and Immuvac among household contacts and high-risk groups.
2. School-Based Vaccination: Focus on adolescents and school-going children.
3. Preventive Therapy: Integration with latent TB treatment programmes.
4. Nutritional Support: Strengthening nutrition interventions for vulnerable populations.
5. Case-Based Management: Improved diagnosis and treatment adherence.
6. Public Health Investment: Sustained funding and surveillance systems.
7. Combination Approach: Multiple interventions rather than reliance on a single vaccine breakthrough.

Conclusion

The PreVenTB Trial offers a promising pathway for strengthening India’s TB elimination efforts through indigenous vaccines and targeted interventions. Achieving the goal of a TB-Mukt Bharat by 2025 and contributing to SDG 3’s target of ending the TB epidemic by 2030 will require a combination of vaccination, nutrition, early detection, and sustained public health action.

Value Addition

Tuberculosis (TB): Key Facts

1. Causative Agent: Mycobacterium tuberculosis
2. Transmission: Airborne droplets
3. Types: Pulmonary TB and Extrapulmonary TB
4. Latent TB: Infection without symptoms; can later progress to active disease
5. SDG Target: End TB epidemic by 2030

National TB Elimination Programme (NTEP)

1. Formerly Revised National TB Control Programme (RNTCP)
2. Based on National Strategic Plan for TB Elimination
3. Uses molecular diagnostics and universal drug susceptibility testing
4. Provides free diagnosis and treatment

Major Government Initiatives

1. Ni-kshay Portal: Facilitates digital tracking of TB patients.
2. Ni-kshay Poshan Yojana: Provides nutritional support to TB patients.
3. TB Mukt Bharat Abhiyan: Supports community participation in TB elimination.
4. PM TB Mukt Bharat Abhiyan: Encourages adoption of TB patients through Ni-kshay Mitras.