Objective To analyze the exposure-response relationship between meteorological factors and hand, foot and mouth disease (HFMD) and its threshold effect in subtropic area in China.

Methods The incidence data of HFMD in subtropic area in China from 2010 to 2019 and local meteorological data during the same period were collected. Spearman correlation test was used to identify the meteorological factors influencing the incidence of HFMD, and generalized additive model was used to analyze the exposure-response relationship and its threshold effect.

Results The incidence rate of HFMD increased in subtropic area in China from 2010 to 2019 (χ²=105.565, P<0.050), with two annual incidence peaks from April to July and from September to October. The male to female ratio of the cases was 1.58∶1, and children aged 0–5 years (94.74%) and children living scatteredly (78.13%) were the mostly affected. The incidence of HFMD had obvious nonlinear relationship with the average precipitation, average temperature, daily temperature difference, atmospheric pressure and relative humidity in the subtropic area. It was found that when the precipitation was less than 5 mm, the average temperature ranged from 15.70 to 23.80℃, the atmospheric pressure was below 969 hPa, and the relative humidity ranged from 71.00% to 78.00%, the incidence risk for HFMD increased by 5.46%, 3.12%, 7.97% and 1.41% respectively for each unit of change, the day and night temperature difference was below 5.60℃, the risk for HFMD decreased by 4.65% for each unit increase.

Conclusion Interventions and health education targeting children aged 0–5 years, especially those aged 0–2 years or living scatteredly and boys, as well as their caregivers, are needed. It is necessary to develop early warning and prevention measures before warm and humid seasons.