Short-term Effects And Prediction Study Of Air Pollutants Corrected By Meteorological Factors On Hand,Foot And Mouth Disease

Objectives:To understand the time-regional-population distribution characteristics of hand,foot and mouth disease（HFMD）and its correlation with meteorological factors and air pollutants in Hefei City from 2014 to 2020.To evaluate the effects of air pollutants in HFMD and quantify the effects in concentration dimension and lag dimension.To fit the best prediction model,so as to reduce the disease burden of susceptible population and health system and to prevent HFMD scientifically.Methods:Based on the daily reported incidence data of HFMD in Hefei City from2014 to 2020,this study combined the same period data of meteorological factors and air pollutants to establish a time series.Used the distributed lag nonlinear model to correct the effects of meteorological factors,so as to explore the correlation effects between air pollutants and HFMD.The effects of air pollutants were combined with the construction of prediction model,the optimal autoregressive integrated moving average（ARIMA）model was determined by Akaike information criterion（AIC）standard.Results:（1）A total of 116 888 cases of HFMD were reported in Hefei from 2014 to 2020,with an average daily rate of 45.71 cases.The annual average incidence was 205.19/100,000.The incidence of HFMD in males was higher than that in females（242.98/100,000 v.s.165.99/100,000）.There were 103 867 cases in children under 5 years old,accounting for 88.86%.The incidence of HFMD gradually decreased.The majority of scattered children,accounting for 68.70%,and children in nursery care accounted for 26.92%.（2）Sulfur dioxide（SO₂）had a risk effect on HFMD in the range of 10～16μg/m³ and RR was up to 1.022 4（12μg/m³）.With an increase of 10μg/m³,and the daily incidence of HFMD increased by 3.70%.The total effect of nitrogen dioxide（NO₂）on HFMD was like a“M”,and there was a risk when the concentration was higher than 5μg/m³.The maximum RR was 1.304 1（53μg/m³）,and an increase of 10μg/m³ could increase the incidence of HFMD by 5.45%.The risk of ozone（O₃）on HFMD showed that the maximum total effect was 1.425 4（26μg/m³）when O₃ was less than 68μg/m³ and 76μg/m³～130μg/m³.The risk of very low O₃ concentration（33μg/m³）on HFMD was 1.040 7 and the risk of HFMD disappeared at high O₃ concentration.The total effect of fine particulate matter(PM_2.5)on HFMD was dangerous when the concentration was lower than 12μg/m³,and the risk tended to decrease with the increase of concentration,with the maximum RR=1.427 7（0μg/m³）.（3）When the concentration of SO₂ and NO₂ increased by 10μg/m³,the sensitivity of male to HFMD was higher than that of female,while the risk of HFMD in female was higher than that in male when the concentration of O₃ increased in the lagged dimension.Compared with≥5 years old group,children younger than 5 years old were more sensitive to increasing SO₂ concentration and decreasing NO₂ concentration.The sensitivity of decreasing SO₂ concentration,O₃ or PM_2.5 concentration to the risk of HFMD was higher in children in nursery care than in children in scattered care.On the contrary,the effect of decreasing NO₂ concentration by 10μg/m³ was higher in children in nursery care.It is dangerous to reduce NO₂,O₃ and PM_2.5 concentration in cold season.（4）A total of 96 models were fitted in this study,among which the model ARIMA（1,0,1）（2,1,0）[52]combined with O₃ concentration data of the same period had the minimum AIC（2 503.29）.And the root mean square error=77.05,mean absolute error=51.09,mean absolute percentage error=23.87.Conclusions:（1）Through the summary and discussion of the research results,it was found that air pollutants:SO₂,NO₂,O₃ and PM_2.5 in Hefei City have impacts on the incidence of HFMD.Males were sensitive to the increase of SO₂ and NO₂ concentration,while females were sensitive to the increase of O₃ concentration.Hence the effects of environmental pollution should not be ignored in the prevention and control of HFMD.It is suggested that the susceptible population,especially the more sensitive population and their guardians should pay attention to the protection and isolation of relevant air pollutants pollution and especially in cold season.（2）The prediction model fitted in this study is conducive to the scientific and accurate prevention and control of HFMD in health departments,and is worthy of application and promotion.In the prediction and prevention work of HFMD carried out with the help of the model,combining some air pollutant data of the same period can better help the prediction.