Surveillance for hemorrhagic fever with renal syndrome in Taizhou, Zhejiang,2009-2015

Objective To understand the incidence trend of hemorrhagic fever with renal syndrome (HFRS) and density and hantavirus carriage of rats in Taizhou, Zhejiang province, from 2009 to 2015. Methods The incidence data of HFRS were collected from national disease surveillance information system. Rats were captured by using traps. Hantavirus was detected using immunofluorescence assay and hantavirus antibodies were detected by using ELISA. Results From 2009 to 2015, a total of 702 HFRS cases were reported in Taizhou and the incidence rate was 1.68/100 000. Most cases occurred in Tiantai, Sanmen and Linhai counties, accounting for 70.94% of total cases. About 81.34% of cases were farmers. There was an obvious correlation between the incidence rate and the density of rats(r=0.963, P=0.001). A total of 1 425 rats in 11 species were captured from 2009 to 2015. The average density of rats was 3.91% and the virus carriage rate was 3.72%. Hantavirus was only detected in the samples from 50 Apodemus agrarius and 3 Rattus norvegicus. Conclusions The incidence of HFRS was low in Taizhou. Apodemus agrarius was the major host animal in this mixed focus. It is necessary to strengthen the HFRS surveillance in Taizhou.