Epidemic Situation Of Hemorrhagic Fever Syndrome And Investigation Of The Host Animal In Some Areas In Yunnan Province,2014-2015

Obiective: To understand the epidemic situation,host,distribution and epidemic characteristics of hemorrhagic fever with renal syndrome(HFRS) from 2014 to 2015, and provide a scientific basis for the monitoring and prevention of HFRS.Methods: The data of HFRS were collected from Yunnan CDC infectious disease reporting system and the relative data were analyzed, by EXCEL2010, SPSS17.0 and Epi Info7.0. The antigen of hantavirus( HV) was detedted by direct immunofluorescence assay(IFA). The viral nucleic acid was amplified by reverse transcription polymerase chain reaction(RT-PCR).The viral sequences were analyzed by DNAstar, Clustal1.83, MEGA6.06.Results: The 510 cases of HFRS were reported in Yunnan Province, 2014-2015. Chuxiong and Dali Prefecture were the highest incidence areas. The main attecked season were summer and autumn. The highest incidence people were the middle-aged male farmers. By the survey of the 253 HFRS cases, the main clinical manifestations were: fatigue, fever and headache.The routine clinical laboratory diagnosis can not be the diagnostic criteria of HFRS cases; HFRS vaccine coverage was- low in the rural areas. The person to person transmission of HFRS cases was not found in Yunnan province; The route of infection was unkown in most cases. The 351 small mammals were captured in Gongshan, Lushui,Chuxion and Dayao in Yunnan Province from 2014to2015. 108 out of 304 were positive by IFA. The positive ratewas 17.59%(19/108) by RT-PCR. By gene-typing 19 the positive, the two strains of HV are the closest to Asikkala virus(ASIV) which of identy was from 63.5% to 79.7% at nucleotide level harbored by Sorex minutus.The one strain of HV begongs to Seoul virus(SEOV) harbored by Niviventer fulvescens. The 12 strains of HV are the closest to the strain of YN06-1024 which of the 11 strains harbored by Eothenomys miletus and 1 strain harbored by Soriculus salenskii.The 4 strains of HV were the closest to the strain of YN05-484 harbored by Anourosorex squamipes.Conclusion: The number of cases was the highest incidence from 2014to2015 in Yunnan since HFRS was surveyed, Prevention and control of HFRS in summer is more important than other seasons.The middle-aged male farmers are the focus population.The general clinical laboratory diagnostic criteria can not diagnose HFRS case. There are biodiversities of HV host animals meanwhile there are genetic diversities of HV harbored by host animals in Yunnan province, too. There are the phenomenon of cross-species among host animals infected by HV in Yunnan province. The host animals, especially insectivors, carry the novel types of HV.