Model-informed evaluation of interventions to eliminate tuberculosis transmission in China

Despite impressive achievements in the control of tuberculosis (TB), the burden of TB in China remains high. Real-time evaluation of interventions can help optimise strategies to eliminate TB. However, the multiple infection routes and heterogeneous distribution of TB make reliable evaluation difficult. This study aimed to examine the distribution of TB in different age groups and evaluate the efficacy of different interventions.

A compartmental SVEIR model was constructed using ordinary differential equations to simulate TB transmission patterns.

A TB model was developed to examine disease distribution in different age groups and to determine the efficacy of different interventions. The model was validated by fitting the Chinese TB incidence data from the Global Burden of Disease (GBD) study from 2001 to 2021. The basic reproduction number (R₀) was calculated, and predictions were made for future TB cases in China using different mitigation strategies. The model was then used to determine the likelihood of achieving the World Health Organisation (WHO) targets for TB elimination.

China has reduced TB incidence from 71.5 per 100,000 population in 2001 to 43.7 per 100,000 in 2021, with an estimated R₀ value of 0.16. By 2035 and 2050, TB incidence in China is expected to be 32.1 and 25.6 per 100,000, respectively; however, the proportion of individuals with TB in the older age group is predicted to increase from 19.1 % in 2001 to 49.3 % in 2050. Reduction of the activation and relapse rates is the most effective intervention for TB control. If both activation and relapse rates are decreased by 90 %, TB incidence would be reduced by 94.54 % of the 2015 level by 2035, thereby achieving the WHO target.

TB control remains an urgent priority in China. It is essential to focus efforts on screening and intervention strategies for both latent and infected individuals, especially in the elderly population.