Objective To analyze the epidemiological characteristics of hemorrhagic fever with renal syndrome (HFRS) in Yunnan province, China and to provide reference for the prevention and control of HFRS. Methods The data on HFRS cases in Yunnan were collected to establish a database using Excel 2003. Statistical analysis was performed using SPSS 13.0 to evaluate the incidence and mortality of HFRS, as well as the geographical, seasonal, and population distributions of the cases; analysis of variance was used to determine the regional differences in incidence, and linear correlation analysis was used to determine the population distribution of HFRS. Results From 1976 to 2012, a total of 876 cases of HFRS were reported in Yunnan province, and 50 cases were fatal; the average annual incidence was 0.058/100 000, the average annual mortality rate was 0.0042/100 000, and the fatality was 5.71%. Two epidemic peaks occurred in 1984-1987 and 1998-2006. The cases of HFRS were reported in 75 county-level regions (counties, cities, or districts) of 14 prefecture-level regions (prefectures or cities) in Yunnan. There were significant differences in the incidence of HFRS among the prefecture-level regions. The main epidemic areas (prefecture-level regions) were Kunming, Honghe, Chuxiong, and Dali, where 80.48% of all cases occurred, and particularly 35.50% of all cases were reported in Kunming. The epidemic areas were distributed in the central and northwestern regions at 1500-2500 m elevation; few cases were reported in the mountainous areas (>2500 m elevation) and low-elevation areas (<1500 m elevation) in the southwestern region. The incidence of this disease was found through the whole year, and the epidemic peak was in spring and summer. Young and middle-aged male farmers were the main affected population. Conclusion HFRS cases are widely distributed in Yunnan province, and the central and northwestern basin areas at 1600-2000 m elevation are the main epidemic areas. The surveillance and control of HFRS should be strengthened in the main epidemic areas.

【Abstract】 Objective To analyze the distribution characteristics of mosquito in Yunnan province and its relationship with the arborvirus such as Japanese encephalitis (JE), and provide the scientific basis for its prevention and control. Methods Mosquitoes were collected from the residential areas and the stables of livestocks in villages at night, and bamboo forests in the day. Results A total of 158 909 adult female mosquitoes were collected, which belonged to 88 species 10 Genera, and were mainly Culex，Anopheles and Aedes, accounting for 56.66%, 25.35% and 13.88% respectively. Among them, as many as 132 081 adult mosquitoes belonging to 63 species 7 Genera were caught in the residential areas at night, in which Cx.triaeniorhynchus has the highest proportion (42.12%), followed by An.sinensis (23.31%). And 26 828 adult mosquitoes belonging to 48 species 5 Genera were caught in the field by day, and the proportion of Ae.albopictu was highest (31.89%), followed by Ae.annandalei（20.21%）. A total of 131 538 female mosquitoes that belonged to 29 species of 8 Genera were divided into 3957 groups. As a result, 81 strains of JE virus were isolated from mosquitoes (17 species 5 Genera). The virus strains isolated from Culex were the most（59 strains）accounting for 72.84%, followed by Anopheles (8 strains ) accounting for 9.88%, and Aedes (9 strains) accounting for 11.11%. Only two  strains  were  isolated  from  Armigeres  and  Mansonia,  accounting   for  2.47%.  About  27  strains  JE  were  isolated  from Cx.triaeniorhynchus, accounting  for   33.33%  of  the  total.  Conclusion The  dominant  species  in  the  residential areas  are  Cx.triaeniorhynchus, An. sinensis,  Cx.fuscocephalus, Cx.whitmorei, Cx.pseudovishnui and An.vagus  at  night,  while  Ae.albopictus,  Ae.pseudalbopict,  Ae.annandalei,  Ae.vexans  and  Ar.subalbatus  were   the  dominant  species  in  the  field  by  daytime. Cx.triaeniorhynchus  and  Ae.albopictus are the main vectors of JE and Dengue fever in Yunnan province, respectively.