Routine Childhood Immunization Coverage and Tuberculosis Incidence in ASEAN and China: Evidence from a Two-Way Fixed-Effects Panel, 2000–2022

Tuberculosis (TB) incidence remains uneven across ASEAN economies and China, reflecting differences in health-system capacity and broader development conditions. This study examines whether routine immunization performance—treated as a measurable proxy for primary healthcare delivery capacity—is associated with TB incidence over time. Using a balanced country–year panel covering 11 economies from 2000 to 2022 (N = 253), the analysis constructs an Immunization Index as the mean of DPT and measles immunization coverage. The outcome is TB incidence per 100,000 population, estimated in both level and logarithmic forms. The empirical strategy combines descriptive association tests with multivariable panel regressions, including two-way fixed effects (country and year) to account for time-invariant national characteristics and common temporal shocks. In pooled and fixed-effects level models, immunization is negative but not statistically significant. In a two-way fixed-effects log specification, immunization is marginally significant (β = −0.0034, p < .10). The preferred lagged log fixed-effects model indicates a statistically significant delayed association: a one-point increase in the prior-year immunization index is associated with approximately a 0.54% reduction in current-year TB incidence (β = −0.0054, p < .01), implying roughly a 5.26% reduction for a 10-point improvement. Electricity access and internet use are consistently negative and significant in log fixed-effects models, highlighting the role of enabling infrastructure and connectivity. Findings support an interpretation of immunization performance as a system-capacity indicator linked to subsequent reductions in communicable disease burden, while recognizing the observational design and limited number of country clusters.