Surveillance of epidemic hemorrhagic fever patients with renal syndrome in Yunnan Province in 2003.

Objective To understand epidemiological characteristics of Hemorrhagic Fever with Renal Syndrome (HFRS) and offer a guidance of control and prevention of HFRS in Yunnan Province. Methods Collecting the data of cases of HFRS in Yunnan Province and collecting human sera and the lung tissue and sera of rodents in the surveillance counties and detecting the antibody and antigen of Hattanvirus. Results 72 cases including 1 death had been reported in Yunnan Province in 2003. The incident rate was 0.17/100 000 and the case fatality rate was 1.39%. The main prevalent areas were Honghe Prefecture, Dali Perfecture, Kunming city and Chuxiong Prefecture. The latent infection rate was 2.94% in population in three surveillance counties: Luxi, Xundian and Yongshen. 11 species of 537 rodents were captured in the three counties. Rodents of Rattus norvgicus and Rattus flavipectus were the dominant species in human living areas and rodent of Apodemus agrarius was the dominant species in the field. The Hattanvirus carrying rate was 3.44% and the vints-carrying rodents were Rattus norvegicus, Rattus flavipectus, Mus musculus, Eothenomys miletus, Apodemus draca and Suncus sp. Conclusion There are the Rattus foci with the hosts of the main rodents of Rattus norvegicus and Rattusfiavipectus, and there are the Apodemus foci with the host of the main rodents of Apodemus draca and Eothenomys miletus insurveillance areas. The increase of the incident rate is correlative closely with the expansion of the epidemic areas. Survelliance in the whole province be strengthened,and the measures of elimination of rodents and vaecination be taken for controlof HFRS.