Epidemic characteristics and genetic analysis of hemorrhagic fever with renal syndrome in an industrial park in Daishan County, Zhejiang Province / 中华地方病学杂志

ABSTRACT

Objective:To analyze the epidemic characteristics and virus gene sequence of hemorrhagic fever with renal syndrome (HFRS) in an industrial park in Daishan County, Zhejiang Province, and to provide clues and basis for local HFRS prevention and control.Methods:According to the case questionnaire in the "National Surveillance Program for Hemorrhagic Fever with Renal Syndrome", general and epidemiological investigation of HFRS cases was carried out in the epidemic-related industrial park. Serum samples of the cases, people and host animals in the same living environment were collected for hantavirus antibody or nucleic acid detection, the M, S gene amplification and sequence determination. MEGAX 10.1.8 software was used to construct the phylogenetic tree of M and S genes for virus genotyping and evolutionary analysis.Results:A total of 3 confirmed cases of HFRS were reported. They were all workers in the epidemic-related industrial park, male, who lived in the park for more than half a year and had no history of HFRS vaccination. There were no rodent-proof facilities in the industrial park's dormitories and canteens, and the living items were placed in a disorderly manner, the rodents and its excrement could be seen; a total of 38 host animals were captured in the same living environment with cases, all of which were Rattus norvegicus. The 3 reported cases of HFRS were all mild, with atypical clinical manifestations in the early stage of onset, mainly fever and fatigue. The serum specific antibodies of hantavirus IgG and IgM were positive (3/3), and the antibodies of people in the same living environment were negative (100.0%, 100/100). The serum samples of 2 reported cases of HFRS and 4 Rattus norvegicus were positive for nucleic acid, all of which were SEOV type hantavirus. The M gene segment homology of 6 positive serum samples was 100.0%, which was closely related to Rod/2012/QHD/4/Gc isolated from Hebei and RuianRn180 isolated from Ruian Zhejiang Province; the homology of S gene segment was 99.6% to 99.8%, which was closely related to JiangxiXinjianRn-09-2011, a strain isolated from Jiangxi Province. Conclusions:The HFRS epidemic in the industrial park is caused by the transmission of SEOV type hantavirus to humans via Rattus norvegicus; poor living environment, poor hygiene habits of personnel and lack of vaccination are all related to the incidence of HFRS; the main epidemic strains shows high homology and geographical aggregation.