Objective To investigate the epidemic situation of hemorrhagic fever with renal syndrome (HFRS) and the surveillance data of host animals in Tiantai county of Zhejiang province, China, and to understand the epidemiological characteristics and changing trend of HFRS. Methods Case surveillance data were collected; the case data in 1984-2003 were collected from the epidemic data archives of Tiantai county, and the case data in 2004-2018 were collected from the China Information System for Disease Control and Prevention. As a national surveillance site, Tiantai county carried out host surveillance and data collection according to national requirements. Excel 2010 and SPSS 17.0 softwares were used to perform a descriptive epidemiological analysis of HFRS epidemic data and surveillance data of host animals, and ArcGIS 10.0 software was used to draw the disease map of townships. Results A total of 6 223 HFRS cases were reported in Tiantai county in 1984-2018, with a mean annual incidence rate of 32.36/100 000; the peak of HFRS epidemic was observed in 1986, with an incidence rate of 206.10/100 000, and then the incidence rate of HFRS decreased rapidly; the incidence rate of HFRS remained at a low level in 2001-2018, with a mean annual incidence rate of 7.01/100 000. The onset seasons of HFRS showed two peaks, with a peak in November to next January (44.08%, 2 743/6 223) and a small epidemic peak in April to June (1 369/6 223, 22.00%). Surveillance data showed that 90.92% (5 658/6 223) of the cases were distributed in 8 plain townships/streets at the Shifeng River Coast of Tiantai county. Most patients were male young adults, and the male/female ratio was 1.66:1 (3 884/2 339). Most patients were farmers (5 553/6 223, 89.23%). The mean density of rodents was 8.87% in 1984-2018, and the mean proportion of virus-carrying rodents was 4.49%. Conclusion The overall incidence rate of HFRS tends to decrease in Tiantai county and maintains at a low level in recent years, and the cases are widely but unevenly distributed and have obvious regional characteristics. Tiantai county is a mixed HFRS epidemic area with Apodemus as the main type of host animal, and there are still high rodent density and virus-carrying rate.

Objective To analyze the epidemiological characteristics of hemorrhagic fever with renal syndrome (HFRS) and the virus-carrying rate of host animals (rodents) in Tiantai county, Zhejiang province, China, and to provide a scientific basis for effective control of HFRS. Methods The data of the epidemic situation of HFRS in Tiantai were analyzed using descriptive epidemiological method. Rodents were captured using traps and then investigated. Indirect immunofluorescence assay was adopted to identify specific IgG antibody. Direct immunofluorescence assay was used to identify hantavirus antigen in the mouse lung. Results A total of 452 cases of HFRS were reported from 2001 to 2011 in the whole county, with 3 deaths, an annual average incidence of 7.27/10 ⁵, and a mortality rate of 0.66%. Throughout the whole county, the incidence of HFRS was primarily distributed in the towns and villages in the plain region at both sides of Shifeng River. This disease occurred in each month throughout the year, with May to July and October to December as high-incidence periods, accounting for 31.19% and 34.29% of all cases. People aged between 26-64 years were most easily infected, accounting for 86.06% of all cases. As for occupation, peasants constituted the majority of all cases, accounting for 82.52%. The ratio of male cases to female cases was 2.90:1. The coincidence rate of clinical diagnosis in these cases was 82.83%; the recessive infection rate of healthy population was 1.27%. The serological positive rate of mice was 5.20%. Apodemus agrarius was the dominating species in the field mice, followed by Rattus losea. R. norvegicus was dominant species in the house mice. The virus carrying rate of the mouse lung was 10.62%. Conclusion HFRS cases occurred every year in Tiantai county, Zhejiang province, China, and the virus carrying rate of host animals was relatively high. Measures should be taken to enhance surveillance and control of HFRS.

Objective To study the epidemiological charactristics of hemorrhagic fever with renal syndrome(HFRS) in Tiantai county for the development of the strategies specific to the prevention and control of the epidemic. Methods Epidemiological investigation into the epidemic situation among human population was conducted by means of the indirect immunofluorescence assay (IFA) for the detection of serum antibody in patients and healthy population. The virus-carrying state of the host animals was determined by Hantaan virus antigen detection with the direct immunofluorescence assay. Results A total of 181 HFRS cases was reported with an average annual incidence rate of 6.39/10⁵ in Tiantai county from 2005-2009. There was an incidence ratio of 2.42∶1 for male and female patients, with peasants affected predominantly accounting for 86.74%. The total density of rodents was 4.87% with an average indoor rodent density of 2.10% and an outdoor one of 5.76%. The average virus-carrying rate of rodents was 7.48% and the serum positive rate of patients was 77.70%. Conclusion Tiantai is a mixed HFRS epidemic area, with the Apodemus-type dominant. Greater efforts need to be made in the surveillance and prevention of the epidemic.

【Abstract】 Objective To investigate the infection of Bartonella in rat?shape animals by molecular technology. Methods Rat?shape animals were captured by night trap in Tiantai county of Zhejiang province. DNA from rat livers were detected by PCR, and the positive products were sequenced. The infection rate of Bartonella in rat was calculated. Results There were 25 positive samples among 55 samples collected. The positive rate of Bartonella infection in Apodemus agrarius and Rattus losea were 48.84% and 33.33%, respectively. The sequence was more similar to B.doshiae. Conclusion The infection rate of Bartonella in rat?shape animals was higher in Tiantai county, and there was risk of transmitting this pathogen to human. The control measure should be figured out. It should take measures to control it.

Objective To study the epidemiological charactristics of hemorrhagic fever with renal syndrome in Tiantai county,Zhejiang province,and make the measures targeting hemorrhagic fever with renal syndrome prevention. Methods Animal hosts in surveillance area were investigated. The serum of the patients were collected to test. Analysis the density and virus carried rate of rodents. Results 165 cases were reported from 2001 to 2003 in whole county,and the annual incidence rate was 9.93/100 000. 1 patient died and the fatality rate was 0.7%. Hemorrhagic fever with renal syndrome was primarily a diease of the male peasants of the youth adults occuring predominantly. Most infections happened from November to January of next year. The average rodents density was 4.53%. The serum positive rate of patients was 81.37%. The virus carried rate of rodents was 16.38%. Conclusion Tiantai county belonges to mixed epidemic area of hemorrhagic fever with renal syndrome and the Apodemus mode is primary. The enhanced surveillance and prevention are necessary.