Short-Term Meteorological Variability and Pathogen-Specific Foodborne Disease Risk in Ningbo, China

Meteorological factors may influence the risk of foodborne diseases (FBDs), but evidence comparing different case definitions and pathogen-specific associations within the same surveillance system remains limited. This study aimed to investigate the relationship between short-term exposure to meteorological factors and FBDs in Ningbo, China. We used data from the Ningbo Foodborne Disease Surveillance System and the daily meteorological data of the Ningbo Meteorological Bureau for time-series analysis. Generalized additive models and distributed lag nonlinear models were used to evaluate the associations adjusted for long-term trends, seasonal changes, day of week, and holidays. A stratified analysis was carried out by sex, age, and pathogens. We found that short-term temperature rise was significantly associated with risk of clinically diagnosed FBD cases (mean: relative risks [RR] = 1.028, 95% confidence interval [CI]: 1.006-1.049; minimum: RR = 1.025, 95% CI: 1.004-1.047). Sex- and age-stratified analyses indicated positive temperature associations in both sexes and in several age groups between 15 and 64 years. Pathogen-specific analyses show that there is a positive relationship for Vibrio parahaemolyticus (mean temperature: RR = 1.087, 95% CI: 1.021-1.157), whereas an inverse relationship for Norovirus (mean temperature: RR = 0.965, 95% CI: 0.938-0.993). The findings remained robust in sensitivity analyses. These findings may inform targeted seasonal and pathogen-specific surveillance.