摘要Objective Hand,foot,and mouth disease(HFMD)transmission is sensitive to temperature-humidity interactions;however,the role of wind speed in modifying these effects remains unknown.This study investigated how wind speed modifies the combined effects of temperature and humidity on HFMD burden and identified subgroups of individuals with increased vulnerability to these climate exposures.Methods We analyzed data from 524,100 HFMD cases and daily meteorological measurements across Guizhou,China,between 2012 and 2019.Disease burden was quantified as the number of years lived with disability.Exposure-response relationships and lag effects were modeled via distributed lag non-linear models.Additive interactions were assessed based on the proportions attributable to the interaction.The effects of sex,ethnicity,and urbanization were examined using stratified analyses.Results Meteorological factors showed synergistic effects on HFMD burden.The peak burden occurred at moderate mean temperatures(8.7-22.8 ℃)combined with high relative humidity(>73.7%),showing a 2.4-fold increase versus the reference.High wind speed(>2.5 m/s)further increased this effect,with a 3.1-fold increase in burden.This joint effect was attributable to the additive interaction involving wind speed and remained robust in stratified analyses that identified heightened vulnerability among boys,minority areas,and urban agglomerations.Conclusion The HFMD burden was highest under specific combinations of temperature and humidity,and further increased with concurrent exposure to high wind speeds.Public health strategies for HFMD prevention should incorporate wind speed monitoring into early warning systems and address vulnerable subgroups,including boys and populations in minority areas and urban agglomerations.