关键词: 集中度, 圆形分布, 肾综合征出血热, 季节特征

Abstract: Objective To get an insight into the characteristics of temporal clustering and distribution of patients with hemorrhagic fever with renal syndrome (HFRS) from 2005 to 2010 in Henan province, with the concentration ratio and circular distribution methods evaluated. Methods The incidence data on HFRS from 2005 to 2010 in Henan province were analyzed by concentration ratio combined with circular distribution. Results The M value of the concentration ratio of HFRS in Henan province from 2005 to 2010 by year was 0.356, 0.243, 0.370, 0.341, 0.489 and 0.746,respectively, with the mean angle of the circular distribution from 2005 to 2010 being 338.21°, 12.47°, 296.03°, 341.19°, 319.87°and 314.42° respectively. Except for the years 2006 and 2007,incidence of HFRS in Henan province took on obvious seasonal characteristics (P＜0.05), with the morbidity peak not at the same time (P＜0.05). Conclusion Obvious seasonal characteristics can be seen in the morbidity of HFRS in Henan province with the peak incidence seen in November and December. There has been a trend of the peak incidence occurring more earlier in recent years．

Key words: Concentration ratio, Circular distribution, Hemorrhagic fever with renal syndrome, Seasonal characteristics