Dynamic Analysis on Epidemic of Hemorrhagic Fever with Renal Syndrome from 1979 to 2004 in Qingdao

Objective The present stody was conduced to know about the epidemic charactedstics and prevalence trend of hemorrhagic fever with renal syndrome in order to guide the prevendon and control of the disease Mnthods Data obtained through monitoring from 1979 to 2004 were analyzed．Results The affected area in Qingdao constantly expanded from south to north between 1979 and 2004．The incidence rate fluctuating between 0.20／lakh and 33.34／lakh with an average of 7.39／lakh．And the mortality rate being 5.16％．Epidemic peaks occurred m 1986 and 1999．With the incidence rate and mortality rate being 33.34／lakh and 4.74％ in 1986 and 14.28／lakh and 1.80％ respectively in 1999．The number of caseg and deaths in the five suburb towns plus Huangdao District accounted for 98.57％ and 95.67％ of the total respectively The annual average incidence rates of the epidemic in Huangdao，Jiaonan，Jiaozhou，Pingdu and Jimo were 35.24／lakh，18.90／lakh，13.58／lakh．9.87／lakh and 6.62／lakh．Mspacdvcly．The winter peak of the disease started from October and reached the highest point in November or December and declined in January of the next year，no obvious peak seen in spring．The epidemic was seen in various age groups from 2 years，the youngest，to 85 years，the oldest．Among the affected，those agedfrom 20 to 60 accountedfor 78.41％ and farmers 83.06％ of the total．With the disease 2.53 times more comnlon in males than in females Apodemus agrarius and Rattus norvegicus were the predominant species in the wild and residential areas respectively It was found by fluorescent antibody assays that Apodemus agrarins，Cricetulus triton，Crlcetuhis barabeusis，Rattus norvegicus and Mus museulus carried viruses with the virus—carrying rate highest in Rattus norvegicus both in residential areas and in the wild Conclusion The prevalence rate of HFRS was still high in some areas of Qiugdao and comprehensive strategies should be taken to reinforce the prevention and control of the epidemic．