India's TB crisis: Research forecasts $146 bn GDP loss and 62 million cases by 2040

India, with the largest national tuberculosis (TB) burden, is projected to experience over 62 million new TB cases and 8.1 million deaths between 2021 and 2040, according to a study published in PLOS Medicine.

The study also highlights a projected GDP loss of US$146.4 billion during this period, presenting a considerable challenge to both public health systems and the economy.

"TB imposes a significant health and economic burden on many populations globally," the authors of the study stated. "In India, this burden is compounded by inadequate funding, which has contributed to the country falling short of global TB reduction targets."

Existing assessments of TB's economic impact fail to fully account for its effect on productivity and economic growth, particularly the complex interactions between epidemiology, demography, and the economy.

The study stresses the need for more evidence to understand how increased investment in TB treatment and control could help address both the health and economic challenges. The researchers developed an integrated macroeconomic-health-demographic simulation model to predict the potential return on investment in TB treatment for India.

"Low-income households will bear larger health and economic burdens, while high-income households will experience greater absolute economic losses," the study's authors explained.

However, the findings suggest that significant reductions in both disease burden and economic impact are possible. By achieving the World Health Organisation's target of 90% case detection, India could reduce the clinical and demographic burdens of TB by 75% to 89%, leading to a reduction of US$120.2 billion in GDP losses. 
Further, the development of a 95% effective pan-TB treatment regimen could reduce the same burdens by 25% to 31% and save an additional US$35.3 billion. Scaling up existing treatment regimens could result in a 20% to 25% reduction in disease burden and save an estimated US$28.4 billion.

The researchers emphasise that improving case detection rates and implementing more effective treatment regimens are essential steps to reducing both the health burden of TB and its economic impact. "Even our least effective, but more accessible, revised TB treatment regimen has the potential to generate US$28 billion in GDP gains," the authors stated.

The study also highlighted the importance of the timeline for achieving these improvements. "The economic benefits of improving case detection rates and scaling up treatment depend on both the feasibility and timeframe over which they can be implemented," the authors noted. While the current model has some limitations, such as not separately modelling drug-susceptible and multidrug-resistant TB cases, the authors suggest these issues can be addressed in future iterations.

The authors have called for more investment in TB control and treatment in India, stating: "There is room for additional investment in TB control and treatment in India. Such investment would reduce the suffering of TB patients while maintaining resource provision across other sectors of the Indian economy, said the authors.