Abstract:

Objective To determine the epidemiological characteristics, long-term trend and regional typing of hemorrhagic fever with renal syndrome (HFRS) in Huludao city, which would provide the basis for development of specific control strategies. Methods Epidemiological data on HFRS in the city were retrieved from the National Noticeable Infectious Disease Reporting System for the analysis. Indirect immunofluorescence assay (IFA) was performed to identify the Hanta viral antigen in rodent lung samples for the calculation of virus-carrying rates. The hemagglutination inhibition test was adopted to serotype the serum samples collected from patients at the recovery stage. Results Remaining at a high level since 1998, the HFRS incidence sharply declined from 2006. An onset peak in spring was noticeable, while the number of cases from February to June accounted for 61.37% of the overall patients. The young and middle-age male farmers were at a high risk of contracting the disease. The rat density and virus carrying rates were high, and the SEO serotype was identified from the recovering patients’ sera samples. Conclusion Noticeable decrease of the HFRS incidence in Huludao city was attributable to large-scale vaccination. The SEO serotype was prevalent in this region, while transformation into mixed-type was not yet observed. It is essential to intensify the rodent prevention and control measures and strengthen the observation of the long-term effect of vaccination among inoculated populations. Supplementary immunization may be conducted when necessary.

Key words: Hemorrhagic fever with renal syndrome, Epidemiology, Typing of endemic areas

摘要：

目的 研究葫芦岛市肾综合征出血热(HFRS)流行特征、长期变化趋势以及疫区分型，以制定有针对性的防制措施。方法 采用流行病学方法研究疫情；实验室采用间接免疫荧光法检测鼠肺汉坦病毒抗原，计算鼠带病毒率；采集HFRS恢复期患者血清，通过血凝抑制试验(HI)进行分型。结果 1998年以来HFRS发病一直较高，2006年开始大幅下降；有比较明显的春季发病高峰，2－6月发病数占总病例数的61.37％；高发人群为青壮年男性农民；鼠密度及鼠带病毒率一直较高；恢复期患者血清检测为家鼠型。结论 葫芦岛市HFRS疫情近年来下降幅度较大，主要与大范围疫苗接种有关；疫区型别为家鼠型，未向混合型疫区转变；应加强灭鼠、防鼠工作，加强既往接种人群长期预防效果观察和必要的强化免疫。

关键词: 肾综合征出血热, 流行病学, 疫区分型