Spatiotemporal trends in tuberculosis incidence in Thailand, 2012–2023: a nationwide, province-level analysis

Background Tuberculosis (TB) remains a major public health challenge in Thailand, a high-burden country undergoing both epidemiological transition and pandemic-related disruption. This study examined temporal and spatial patterns of age-standardized TB incidence from 2012 to 2023 across Thailand’s 13 health regions and 77 provinces. Methods National tuberculosis surveillance data were used for all analyses. Age-standardized incidence rates (ASR) were calculated using the WHO World Standard Population (2000–2025). Temporal trends were assessed using Joinpoint regression to estimate Health region–specific annual percent change (APC) and average annual percent change (AAPC). Generalized Additive Models (GAM) were fitted to validate the temporal trajectories. Spatial clustering was evaluated using Global Moran’s I and Local Indicators of Spatial Association (LISA), applied to provincial AAPC values. Results National TB incidence declined substantially from 2012 to 2023, although marked regional heterogeneity persisted. Five regions demonstrated the strongest long-term reductions: region 3 (AAPC − 20.51, 95%CI: −33.00 to − 13.77), region 9 (− 19.42, 95%CI: −28.98 to − 8.57), region 4 (− 17.53, 95%CI: −23.64 to − 12.89), region 11 (− 11.79, 95%CI: −22.16 to − 0.04), and region 13 (− 11.19, 95%CI: −22.44 to − 3.74). Several regions exhibited biphasic trends, including region 6, which showed an early decline followed by stabilization, and region 12, which experienced a mid-period increase before a post-2019 reduction. Spatial analysis revealed limited global clustering, but LISA identified distinct local patterns. Three provinces (Phayao, Phetchabun, Yasothon) formed high-high clusters with increasing AAPC values, while four provinces (Buri Ram, Ang Thong, Nakhon Pathom, Bangkok) formed low-low clusters with sustained declines. High-low and low-high outliers highlighted further geographic heterogeneity. Conclusions Thailand has achieved substantial reductions in TB incidence over the past decade however, pronounced regional and provincial disparities persist. Localized hotspots and divergent temporal trajectories underscore the need for geographically targeted monitoring, equitable resource allocation, and pro-poor interventions to sustain progress toward TB elimination.