Temperature-based spatiotemporal heterogeneity of hand, foot, and mouth disease transmission in China.

BACKGROUND: Hand, Foot, and Mouth Disease (HFMD) remains an important public health issue in China with numerous studies showing significant association between temperature and the disease. Amid growing concerns of the impact of climate change on disease, we specifically explore the relationship between temperature and HFMD in mainland China to investigate and estimate key epidemiological parameters and potential heterogeneity. METHODS: We developed an integrated modeling approach that combined HFMD incidence data from 68 cities across 28 Chinese provinces and municipalities from 2013 to 2019 and temperature data with the Susceptible–Exposed–Infectious–Recovered (SEIR) transmission model and Iterated Filtering (IF2) data assimilation. The approach estimated key epidemiological parameters and quantified the impact of temperature on HFMD transmission in different regions. RESULTS: HFMD transmission characteristics varied considerably by regions. The basic reproduction number ([Formula: see text]) declined spatially from the southeastern coast to the northwestern inland areas, with a maximum of 3.11 in South China, and minimum of 1.49 in Northeast China. The optimal temperature range for HFMD transmission was between 13.61 °C and 29.48 °C, with statistically significant regional differences in these ranges. CONCLUSION: The SEIR-IF2 model accurately fit the observed outbreak patterns and estimated key epidemiological parameters. Furthermore, it identified the optimal temperature range and revealed spatial heterogeneity in HFMD transmission in mainland China, providing a scientific basis for developing targeted prevention and control strategies.