Associations of air pollution and pediatric influenza and the effect modification of temperature

Air pollutants have been identified as risk factors for influenza. However, the role of temperature in modulating the relationship between air pollutants and influenza remains not fully elucidated. Pediatric influenza, air pollutant and meteorological data were collected from 2019 to 2023 in Nanchang City. Distributed lag nonlinear models (DLNMs) were used to analyze the association between air pollutants and influenza, and temperature stratification was used to explore the moderating effect of temperature. A total of 53,716 cases were included in this study. For each 10 μg/m³ increase in PM2.5 and PM₁₀ at lag 2, SO₂ at lag 1 and NO₂ on the day of the visit, the relative risk (RR) were 1.038 (95% CI: 1.011-1.065), 1.124 (95% CI: 1.079-1.170), 1.014 (95% CI: 1.003-1.024) and 1.048 (95% CI: 1.001-1.098), respectively. Boys and the 6-14 years group were more sensitive to PM2.5 and PM₁₀, whereas girls and the 2-3 years group were more sensitive to SO₂, NO₂ and O₃-8 h. High temperatures enhanced the effects of PM2.5 and PM₁₀, whereas low temperatures enhanced the effects of SO₂. Temperature affects the association between air pollutants and pediatric influenza, which provides new insights into pediatric influenza surveillance and early warning.