Effects of daily mean temperature on the incidence of other infectious diarrhea in Hebei Province / 中华传染病杂志

ABSTRACT

Objective:To explore the lag effect and correlation between daily average temperature and the incidence of other infectious diarrhea in Hebei Province.Methods:The data of meteorological factors (including temperature and average daily temperature) and the daily incidence of other infectious diarrhea in Zhangjiakou City, Chengde City, Tangshan City, Qinhuangdao City, Baoding City, Langfang City, Cangzhou City, Shijiazhuang City, Hengshui City, Xingtai City, and Handan City in Hebei Province from 2017 to 2020 were collected. Eleven prefecture-level cities were divided into four regions, including east, north, middle and south regions. Distributed lag non-linear model was applied to examine the non-linear associations and the lag effect of daily mean temperature on daily incidence of other infectious diarrhea. Meanwhile, the cold and hot effects were used to estinuate the lag-response relationship on the incidence of other infectious diarrhea.Results:A total of 231 008 cases of other infectious diarrhea were reported in Hebei Province. The seasonal distribution was obvious, showing a bimodal distribution of large peaks in summer and small peaks in winter. An inverse S-shaped association between average daily temperature and cumulative risk ratio ( RR) of other infectious diarrhea was observed in Hebei Province. Both high temperature (higher than 27.50 ℃) and low temperature (less than 13.67 ℃) could increase the risk of other infectious diarrhea. When the temperature was lower than 13.00 ℃, the lag time and RR had a U-shaped association (lag four to seven days, 23 to 30 days). Meanwhile, when it was higher than 13.00 ℃, it had an inverted U-shaped association (lag 5 to 21 days). A comparison of four regions of Hebei Province showed that the lag time from south to north was extended from six days to 30 days at low temperature effects with temperature P5=-7.24 ℃. When the temperature getting hot ( P95=28.25 ℃), the risk occurred at lag 0 days, and the lag time gradually got short from north to south. Thus, the high temperature effect reached maximum quickly with a relative short duration. Conclusions:The inverse S-shaped non-linear association between daily average temperature and the incidence of other infectious diarrhea in Hebei Province is observed. Both low temperature and high temperature are associated with increased risk of other infectious diarrhea. But the impact of low temperature is more notable, which has a relative long duration.