Estimating the potential health and economic impacts of new tuberculosis vaccines under varying delivery strategies in Delhi and Gujarat, India: a modelling study.

BACKGROUND

India has the largest tuberculosis burden, but the all-age prevalence in 2021 ranged from 747/100,000 in Delhi to 137/100,000 in Gujarat. No modelling studies have compared the potential impact of new tuberculosis vaccines in regions with differing disease and infection prevalence.

METHODS

We used modelling to simulate hypothetical scenarios of introducing M72/AS01 (with 50% efficacy to prevent disease) and BCG-revaccination (with 45% efficacy to prevent infection) in Delhi and Gujarat.

FINDINGS

The hypothetical M72/AS01 scenario could avert 16.0% of cases and 14.4% of deaths in Delhi, and 8.5% of cases and 7.6% of deaths in Gujarat between 2025 and 2050. The hypothetical BCG-revaccination scenario could avert 8.8% of cases and 8.3% of deaths in Delhi, and 5.1% of cases and 4.8% of deaths in Gujarat between 2025 and 2050.

INTERPRETATION

Additional trials for both vaccines are underway, which will provide further evidence on the vaccine efficacy and narrow the range of uncertainty on the estimates.

FUNDING

Bill & Melinda Gates Foundation (INV-001754).