A Study On The Influence Of Average Temperature And Relative Humidity On Hand,Foot And Mouth Disease In Shanghai,China

According to the fifth IPCC report,the average global temperature will increase by 1.5℃ higher than the industrial revolution by 2052.With global warming,Evidence show that there is a link between climate change and infectious diseases.Meteorological factors will affect hand,foot and mouth disease.Shanghai is one of the most developed cities in China,so it is necessary to study the impact of meteorological factors on hand,foot and mouth disease in Shanghai.In this paper,we analyzed and characterized the daily meteorological factors data from January 1,2012 to December 31,2016 and the daily number of outpatients on hand,foot and mouth disease.Then we use the distributed lag nonlinear model(DLNM)to study the effects of average temperature and relative humidity on the hand,food and mouth disease in Shanghai.At the same time,we consider the effect of average temperature and relative humidity of the 0-21 day on the hand,foot and mouth disease,and the impact on different ages(0-3 years,3-6 years and ≥6 years)and genders.The generalized additive model(GAM)is used to study the effect of the synergistic effect of average temperature and relative humidity on hand,foot and mouth disease in Shanghai.The main findings are as follows.(1)The number of outpatients on hand,foot and mouth disease cases in Shanghai is the highest in summer and the lowest in winter.The number of outpatients on males is greater than females,and the number of outpatients on0-3years is higher than others.The number of outpatients on hand,foot and mouth disease in Shanghai is significantly positively correlated with average temperature,relative humidity and sunshine hours,and is negatively correlated with wind speed.(2)The exposure-response relationship curve between average temperature and the number of outpatients on hand,foot and mouth disease shows an inverted "V" shape.As the average temperature increases,the relative risk(RR)of outpatients on hand,foot and mouth diseases increases firstly and then decreases.The accumulative relative risk of hand,foot and mouth disease decreased firstly and then increased with the increase of average temperature.The effect of high temperature on the hand,footand mouth disease is more durable and delayed.The low temperature has a greater impact on the hand,foot and mouth disease in a short period of time.The average temperature affects males more than females,with the greatest impact on 0-3years and the least impact on ≥6years.When the average temperature are 75% and 99%,and the cumulative lag effect on hand,foot and mouth disease are relatively large.The effect of the average temperature on hand,foot and mouth disease is higher in summer and lower in winter.(3)The exposure-response relationship curve between relative humidity and the number of outpatients on the hand,foot and mouth disease also shows an inverted "V" shape.With the increase of relative humidity,the relative risk of the number of outpatients on hand,foot and mouth disease increased firstly and then decreased.The low relative humidity has a greater impact on the hand,foot and mouth disease at the early and the late stages of lag.while high humidity has a greater impact on the hand,foot and mouth disease at the day and the middle stage of lag.The cumulative lag effect of the relative humidity on hand,foot and mouth disease was larger at lag21..The impact of relative humidity on hand,foot and mouth disease is higher in summer and lower in winter.(4)Synergistic display of temperature and relative humidity shows that with the average temperature and relative humidity increasing,the number of outpatients on hand,foot and mouth disease increases.There is a peak when average temperature and relative humidity are high.The impact of high temperature and high relative humidity on gender is not much different,and the impact on ≥6years is much greater than the others.Under the synergistic effect of average temperature and relative humidity,the average temperature affects females more than males.The effect on3-6years and ≥6years is greater than 0-3years.The impact of the average temperature at high relative humidity is greater than at low relative humidity.Under the synergistic effect of average temperature and relative humidity,the impact of high relative humidity is greater than the impact of low relative humidity.The relative humidity affects males more than females,and the impact on ≥6years is greater than the others.The relative humidity at high temperature affects the hand,foot and mouth disease much higher than at low temperatures.(5)The typical plum rains study found that the average temperature during the plum rains period was about 25℃,the relative humidity was above 80%,and the hospitality index during the plum rains was much higher than the average hospitaladmission index in summer.