Epidemiological Studies Of HFRS In China,2007-2011

This study analyzed the surveillance data on hemorrhagic fever with renal syndrome(HFRS) including the epidemiological characteristics and trend of the diseases.I. Epidemic situation and surveillance on hemorrhagic fever with renal syndrome in China,2007-2011Objective To analyze the surveillance data on including the epidemiological HFRS characteristics and trend of the disease, from2007to2011. Methods Descriptive methods were conducted to analyze the surveillance data from2007to2011which were collected from the internet-based National Notifiable Disease Reporting System. Results From2007to2011, a total of49152HFRS cases and589deaths were reported in China with the average annual incidence rate of0.74/lakh and case fatality rate of1.19%. Morbidity and mortality had been annually decreasing from2007to2009but had been increasing since2010. The top8provinces with HFRS cases were Heilongjiang, Shaanxi, Shandong, Jilin, Liaoning, Hunan, Zhejiang and Jiangxi, which had a accounted for80.5%of the total number of cases. More cases were reported in spring and autumn-winter season, with the peak in November. Reported cases were mainly clustered in15-60age group and in males were3.13times of the females. Farmers were still under the highest risk. Conclusion HFRS cases were widely distributed in most provinces of China, but mainly focused on certain areas and had obvious seasonal peak. Population characteristics and seasonal fluctuation had been changing.II. Epidemiological studies in Shandong Qingdao HFRS2011-2012.To study the HFRS cases in Qingdao JiaoNan2011and the captured rodents in Qingdao in the year of2012, and the Hantavirus sero types and genetic characteristics carried by these human cases and rodents. Methods40HFRS human cases are detected for IgM、IgG and Enzyme-Linked Immunosorbent Assay-Format Microneutralization Test (MNT). Rodents were captured in JiaoNan,LaiXi,JiMo,LaoShan, JiaoZhou and PingDu. Then we extracted RNA and geno typing of Hantavirus carried by the rodents, and sequenced the partial S segments to make the sequence alignment. Altogether629rats were captured in these five areas in2012.The outdoor hosts of Hantavirus in QingDao2012were mainly Apodmus agrarius, Cricetulus barabcnsis Pallas and Cricetulus triton. And indoor hosts were mainly Rattus norvegicusand Mus musculus.7.5%of these rodents carried Hantavirus nucleotide by Real Time PCR, and the results of virus genotyping was39cases of Hantaan virus and8cases of Seovirus. The sequence alignment results of the partial S segments showed that these sequences had the highest homology with84FLi Hantaan viruses group (H5) and with Pf26Seo viruses group (S3) respectively. Comprehensive strategies should be taken to renforce the prevetion and control of the epidemic in Qingdao area.