Environment Factors And Rodent Community Composition Are Associated With Risk Of Hantavirus Infection In Shaoyang And Loudi

Hemorrhagic fever with renal syndrome(HFRS)is a rodent-borne disease.Symptoms include fever,headache,hypotension,multisystemic hemorrhage and acute renal failure.China’s incidence of HFRS is the highest in the world,accounting for 90% of global cases,and 30,000-60,000 cases are reported in China.Since the first HFRS case was detected in 1963,Hunan Province has become one of the most severe endemic areas in China,with more than 90% of the cities have reported infections.Shaoyang and Loudi were the focus of HFRS epidemic area of Hunan province,and the cumulative HFRS cases have more than 10000 cases in last two decades,accounting for over 29% of the total number of cases the province,and it has become a serious public health problem.The distribution,transmission and prevalence of HFRS are influenced by environmental factors and socio-economic factors such as human activities.In this study,data on human HFRS cases and demographic data in Hunan were collected.Spatial scan statistic was used to analyze the spatio-temporal distribution of HFRS cases.Then,rodent communities and environmental factors in clusters(Loudi and Shaoyang)were collected,matrix network analysis and logistic regression combined with geographic information systems(GIS)and remote sensing(RS)were used to identify the rodent community composition and environment factors influenced human hantavirus infection and potential risk of hantavirus infection in different land use types.The content and results were as follows:(1)Space-time clusters of HFRS in Hunan Province.HFRS incidence was high in winter(from November to January)and HFRS incidence varied seasonally.Space-time cluster analysis of HFRS in 2006–2015 in Hunan Province revealed that the primary cluster regularly occurred in Loudi and Shaoyang.(2)Space-time distribution of HFRS in Shaoyang and Loudi.On time scale,HFRS incidence overall presented a downward trend,and locally showed “N”(first rise and fall rise and fall again)trend.Specifically,the annual distribution of cases indicated the highest incidence was in 2007;lower incidence in 2009,but 2013 there was a higher incidence in Shaoyang and Loudi.In the spatial scales,HFRS incidence showed clustering.In detail,Shaoyang city the spatial cluster concentrated in the northeast.The spatial clustering of HFRS infections in Loudi concentrated in the central region and southeast.(3)The risk of hantavirus infection in different environments in Shaoyang and Loudi.HFRS cases occurred predominantly on cultivated land,followed by urban areas,forests and grassland areas.Few cases were identified in water covered areas(lakes,rivers etc.)in both Shaoyang and Loudi.Each land use type has a predominant rodent species.In the current study,the main risk of hantavirus infection in forests and urban areas might be caused by Rattus flavipectus and Mus musculus,respectively in both two cities.Different environmental factors influenced the same rat species spread virus in different regions.NDVI has mainly effect on R.flavipectus and M.musculus carrying hantaviruses in Shaoyang;and relative humidity influenced M.musculus carrying hantaviruses in Loudi.In Loudi,Apodemus agrarius was the predominant species and there were also a number of other rodent species;the risk of hantavirus infection was concentrated in areas with cultivated land and might be caused by Rattus.norvegicus.It represented that Loudi may be a mixed type epidemic area.R.norvegicus carrying hantavirus was influenced NDVI.In Shaoyang,R.norvegicus and A.agrarius were the predominant species,and there were also a number of other rodent species;Cultivated and urban areas had higher risk of hantavirus infection,and these areas were predominantly inhabited by A.agrarius and M.musculus,respectively,indicating that Shaoyang may be a mixed-type epidemic area.TVDI have effect on A.agrarius carrying hantaviruses.Based on the change in rodent community composition and HFRS distribution in different landscapes over a relatively long period of time,the study effectively identified the dominant rodent species for different land use types in areas with HFRS and explored hantavirus transmission of rodent species composition was influenced by environmental factors.The change in rodent community composition is associated with risk of hantavirus infection in different land use types.This study will be useful for the development of regional HFRS incidence monitoring programs and for the prevention of HFRS in different geographical environment,providing reference for the investigation of other similar infectious diseases.