Association of air pollutants and meteorological factors with tuberculosis: a national multicenter ecological study in China

The impact of weather variability and air pollutants on tuberculosis (TB) has been a research hotspot. Previous studies have mostly been limited to a certain area or with a small sample size of cases, and multi-scale systematic studies are lacking. In this study, 14,816,329 TB cases were collected from 31 provinces in China between 2004 and 2018 to estimate the association between TB risk and meteorological factors and air pollutants using a two-stage time-series analysis. The impact and lagged time of meteorological factors and air pollutants on TB risk varied greatly in different provinces and regions. Overall cumulative exposure–response summary associations across 31 provinces suggested that high monthly mean relative humidity (RH) (66.8–82.4%, percentile_56-100 (P_56–100)), rainfall (316.5–331.1 mm, P_96–100), PM_2.5 exposure concentration (93.3–145.0 μg/m³, P_58–100), and low monthly mean wind speed (1.6–2.1 m/s, P_0–38) increased the risk of TB incidence, with a relative risk (RR) of 1.10 (95% CI: 1.04–1.16), 1.10 (95% CI: 1.03–1.16), 2.08 (95% CI: 1.18–3.65), and 2.06 (95% CI: 1.27–3.33), and attributable risk percent (AR%) of 9%, 9%, 52%, and 51%, respectively. Conversely, high monthly average wind speed (2.3–2.9 m/s, P_54–100) and mean temperature (20.2–25.3 °C, P_79–96), and low monthly average rainfall (2.4–25.2 mm, P_0–7) and concentration of SO₂ (8.1–21.2 μg/m³, P_0-16) exposure decreased the risk of TB incidence, with an overall cumulative RR of 0.92 (95% CI: 0.87–0.98), 0.74 (95% CI: 0.59–0.94), 0.87 (95% CI: 0.79–0.95), and 0.72 (95% CI: 0.56–0.93), respectively. Our study provided insights into future planning of public health interventions for TB.