India, world failed to meet WHO End-TB milestone 2020: Lancet study

New Delhi: India's tuberculosis incidence dropped marginally by 0.5 per cent between 2015 and 2020 and failed to meet the World Health Organization's (WHO's) END-TB milestone for 2020, according to new global research published in The Lancet Infectious Diseases journal.

The WHO End TB Strategy aims for a 90 per cent reduction in TB deaths and an 80 per cent reduction in the incidence rate by 2030, compared to the baseline figures of 2015. The 2020 milestones include a 20 per cent reduction in the TB incidence rate and a 35 per cent reduction in deaths.

The latest study estimated that the incidence of TB across all ages in India was 213 cases per one lakh population in 2020, well above the WHO's milestone figure (for India) of 171 per one lakh population. Deaths due to bacterial infectious disease in the same year were estimated to be between 3.5-5 lakh, again much above the mortality milestone of 2.7-3.2 lakh set for India.

The study comes ahead of World Tuberculosis Day on March 24.

Despite accelerated progress in reducing the TB burden over the past decade, the world failed to attain the first interim milestones of the WHO End TB Strategy in 2020, said the researchers forming the Global Burden Disease (GBD) 2021 Tuberculosis Collaborators. The pace of decline has also differed across age groups, with adults aged 50 years and above having the slowest progress.

Of the 204 countries analysed by the team, 15 met the 2020 TB incidence milestone, while 17 met the mortality milestone. Of the 15, 11 were in sub-Saharan Africa, the researchers said.

Novel case-finding interventions in countries like Nigeria, Tanzania, Cameroon and Kenya helped reduce incidence, and were further supported by improved drug coverage in treating HIV across many countries in the sub-Saharan African region, they said.

Only 17 countries achieved the 2020 End TB mortality milestone and drug resistance could be an important factor, according to the researchers.

An "efficacious, safe, and shorter" regimen for treating drug-resistant TB, endorsed by WHO, could have helped reduce deaths, they said. They were referring to the WHO's updated recommendations on treating drug-resistant TB issued in 2020, amidst antibacterial resistance emerging as a major public health threat.

The team also acknowledged the efforts of national social protection interventions in Moldova and Ecuador - two of the 17 countries - that "markedly increased treatment adherence", and "potentially prevented drug resistance".

Around the world, children under 15 years of age were seen to have the largest reductions in TB burden, with incidence falling by 16 per cent and deaths by 34 per cent between 2015 and 2020, even as the burden still remains high in children, according to the authors.

Citing evidence from recent research, they said most of the bacterial disease's transmission occurs outdoors and hence, integrating contact tracing with community-based strategies of screening and prevention will be "particularly important for continued progress".

Globally, adults aged 50 years and above were found to make up 37 per cent of all TB incident cases and 58 per cent of all TB deaths in 2020, and targeting these age groups would be required to meet End TB targets, the researchers said.

Screening and treating older adults for latent tuberculosis - where symptoms do not present themselves - would be essential. Further, given their high chances of adverse reactions to treatment, the researchers highlighted the importance of developing shorter, less toxic treatments, along with early diagnosis, for achieving the End TB targets.

Regarding the COVID-19 pandemic's impact on the global TB burden, the researchers cited limited empirical data and underscored the need for continued research, even as they acknowledged many models to have predicted hundreds of thousands of additional TB deaths due to the pandemic.

The GBD study is the largest and most comprehensive effort to quantify health loss across places and over time, according to the Institute for Health Metrics and Evaluation (IHME), University of Washington (UW), US, which coordinates it.