The Epidemiological Characteristics And Influencing Factors Of Hemorrhagic Fever With Renal Syndrome(HFRS) In Wei-fang City Of Shan-dong Province

Objective:Hemorrhagic fever with renal syndrome(HFRS)is an infectious disease caused by the Hantavirus,which has a long epidemic history and an epidemic area widely in China,is always one of the important infectious diseases.The incidence of HFRS was up to 33.29/100 000,the mortality rate was more than 10%in the epidemic year,which was a huge damage to the health of people and the economic society.Therefore,to master the epidemic law of HFRS accurately and timely,that will provide basic to the scientific formulation and effective implementation of health policy.To describe the epidemic law and distribution area of HFRS in WeiFang during 1974-2016,analysis the prevalent district and epidemic characteristic.To explorer the expansion process of epidemic area and the change types of focus.To investigate the situation of the rats virus carried rate and the meteorological factors that has been brought considerable effect to the epidemic of HFRS,which will provide scientific basic for the control of HFRS.Methods:To collect the surveillance date of HFRS in WeiFang during 1974-2016,and to analysis the incidence trend and the temporal and spatial distribution of HFRS,so as to investigate the expansion process of epidemic area and the change types of focus.To collect the date of HFRS patient that download from the infectious disease report and management system during 2005-2016,so as to analysis the epidemic characteristic of the high prevalence area since 2005.To collect the rat density data during 2013-2016 and the host animal surveillance data during 2003-2016,to analysis the variety composition of rats,and to calculate the virus index with density and virus.carried rate of rats,then to carry on correlation and regression analysis with the virus index of rats and the incidence of HFRS.To collect the data of mean temperature,precipitation,average relative humidity,average barometric pressure and sunshine duration monthly and yearly in LinQu,QingZhou and ZhuCheng,then to carry on the correlation analysis with these data and incidence of HFRS monthly and yearly in LinQu,QingZhou and ZhuCheng.Results:The first case of HFRS in WeiFang was reported in 1974,according to epidemic law,the epidemiology history of HFRS in WeiFang could be divided into five stages:sporadic stage→the first outbreak stage→the second outbreak stage→decreased stage→the third tiny epidemic stage.Simultaneously,the type of epidemic area has been changed:field-rat type→field-rat type mainly and house-rat type subsidiarily→house-rat type mainly and field-rat type subsidiarily→field-rat type mainly and house→rat type subsidiarily.The first outbreak stage concentrated in LinQu and QingZhou,where are in the hilly country in the southwest of WeiFang,ChangYi and HanTing also reported case of HFRS in the northeast of WeiFang.The second outbreak stage focus on ChangLe,and southwest and northeast of WeiFang also reported case of HFRS.The third tiny epidemic stage further extended,the southeast,southwest and northwest of WeiFang reported most cases of HFRS,the north of WeiFang took second place,the city center of WeiFang seldom reported case of HFRS.Since 2005,high incidence countries of WeiFang were LinQu,QingZhou and ZhuCheng,and the epidemic law was different.Epidemic situation of HFRS distributed 117 township of WeiFang during 2005-2016,ZhuCheng town of ZhuCheng country,JiuShan town of LinQu country,MiZhou town of GaoMi country,WuJing town of LinQu country and XinZhai town of LinQu country cumulative reported case were the first five place.We used the data of host animal surveillance and reported case of HFRS to carry on correlation and regression analysis,found that there was a correlation between virus index of rats and the incidence of HFRS.The meteorological factors and the incidence of the generalized additive model shows that there are relativity between the average temperature,average relative humidity,precipitation,sunshine time and the incidence of HFRS.And this relationship has its own threshold value.The prediction results and the actual value of the model fit well.Conclusion:The epidemic situation of HFRS have been controlled well through preventing and eliminating rats,improving the residential environment and inoculating vaccine and so on,but the epidemic characteristic of HFRS and the country that had high incidence of HFRS have been changed a lot,the type of epidemic area also changed by the time regularly,so we should change the prevention and control measures according to the new epidemic law.Through correlation and regression analysis,we found that virus index of rats had a significant correlation with incidence of HFRS,so controlling the density and decrease the virus carried rate of rats could reduce the incidence of HFRS;The influence of meteorological factors brought to different epidemic area were inconsistently.