Objective Moving epidemic method (MEM) was used to estimate the epidemic threshold of hand, foot and mouth disease (HFMD) in Gansu province for the establishment of the early warning standard of epidemic intensity and provide scientific basis for the prevention and control of HFMD.

Methods The incidence data of HFMD weekly reported in Gansu from 2015 to 2023 were collected from Chinese Disease Prevention and Control Information System, and two epidemic seasons were set in a year. The incidence data of HFMD during 2015-2023 and 2015-2019 were used as historical data sets, the epidemic threshold and intensity threshold of HFMD in Gansu were calculated by MEM, and the early warning effect was evaluated by cross validation method.

Results The early warning effect of the model established based on the historical data from 2015 to 2019 was better than that of the model established based on the historical data from 2015 to 2023. The epidemic threshold of the main peak in summer was 160 cases, the medium epidemic intensity threshold was 550 cases, the high epidemic intensity threshold was 850 cases, and the superior high epidemic intensity threshold was 1 031 cases. The sensitivity, specificity and Youden’s index of early warning in epidemic periods were 92.77%, 83.64% and 75.41%, respectively. The epidemic threshold of sub-peak in autumn was 63 cases, the medium threshold was 158 cases, the high epidemic intensity threshold was 390 cases, and the superior high epidemic intensity threshold was 581 cases. The sensitivity, specificity and Youden’s index of early warning were lower than those of main peak in summer.

Conclusion The model effect could be improved by excluding the years in which the number of reported cases was abnormal in the historical baseline. The establishment of early warning models of HFMD by MEM could realize the graded early warning of epidemic intensity of HFMD in Gansu and provide scientific basis for the early warning, prevention and control of HFMD.