Study on comprehensive monitoring of mouse and effect of hemorrhagic fever with renal syndrome vaccine in high prevalence areas of natural focus infectious disease of Zhejiang province in 1994--2010 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the comprehensive monitoring mechanism of mouse and the effect of hemorrhagic fever with renal syndrome (HFRS) vaccine in the high prevalence areas of natural focus infectious disease of Zhejiang province in 1994 - 2010.</p><p><b>METHODS</b>The night trapping method was used to monitor the population proportion, density and the rate of hantavirus (HV) carriers in mice in Xikou township Longyou county in August and September from 1994 to 2010. The healthy residents in Xikou township aged 16 to 60 years were recruited. The subjects were randomly selected as vaccination group and control group according to age, sex, occupational distribution (10 178 in intervention group and 16 159 in control group). Intervention group was given purified and inactivated vaccine from suckling mouse brain, while the control group received no intervention. The prevention effect was evaluated by protective rate of vaccine.</p><p><b>RESULTS</b>The mouse population was stable in the sixteen years and the apodemus agrarius was the main type (76.5% (564/737)). The average density of mouse was 4.73% (1170/24 727). The average rate of virus carrier of mouse was 3.87% (41/1033). In 1994 - 1995, the density of mouse was 22.82% (186/815) and the rate of virus carrier was 7.0% (10/143). In 2009 - 2010, the density of mouse decreased to 2.75% (119/4330) and the rate of virus carrier was 5.5% (13/237). The average antibody positive rate of mouse from 2005 to 2010 was 4.8% (35/728) and the rate was 4.4% (6/138), 0.0% (0/113), 11.8% (16/136), 1.0% (1/104), 3.7% (4/109) and 6.3% (8/128) in each year (P < 0.01). The protective rate of HFRS vaccine was 96.2% (1 case in intervention group and 41 cases in control group).</p><p><b>CONCLUSION</b>The density of mouse decreased significantly in Zhejiang province. The rate of virus carrier of mouse is stable. The vaccine is effective.</p>

Study on the integrated monitoring program regarding mouse and main mouse-borne disease in Zhejiang province / 中华流行病学杂志

Objective To study the integrated monitoring program regarding mouse and plague, hemorrhagic fever of renal syndrome(HFRS)and leptospirosis. Methods Integrated monitoring plan was used. A designated office coordinated 5 departments' actions within the Zhejiang Provincial Center for Disease Control and Prevention(CDC). Cage-trapping method was conducted to monitor the density of mice from June to October, respectively. Results Lishui municipal CDC had finished the integrated monitoring program on mouse and mouse-borne disease while the Longyou CDC had finished the field investigation, using the integrated monitoring program.Specimens were sent to provincial CDC. The integrated monitoring program needed more number of personnel and better coordination. Lishui reported 3 leptospirosis cases and 58 HFRS cases in 2009,with the incidence rates as 0.13 and 2.44 per 100 000, respectively. Longyou reported 2 leptospirosis case and 1 HFRS cases in 2009, with the incidence rates as 0.49 and 0.25 per 100 000, respectively.Lishui and Longyou had no plague case. Lishui caught 91 mice in 2009 and the density was 4.17%.Longyou caught 37 mice in 2009, with the density as 1.18 percent. Most mice caught from Lishui were Apodemus agrarius and the next was Mus musculus. In Longyou the Rattus tanezumi ranked the first, followed by Apodemus agrarius. The positive rate of HFRS antigen in Lishui and Longyou were 10.42% and 4.59% respectively. The positive rate of HFRS antibody in Longyou was 3.70%. The culture positive rate of leptospirosis in mouse renal of Lishui and Longyou were 0 and 0.98%respectively. The culture positive rate of leptospirosis in pig renal, duck renal, frog renal and cattle urine of Longyou was 0. The culture positive rate of leptospirosis in duck blood of Longyou was 80%.Conclusion The integrated monitoring program on mouse and mouse-borne disease seemed to be feasible and could promote the integrated surveillance and control program on mouse and mouse-borne diseases in China.

Study on a 10-year protective effects of vaccination against hemorrhagic fever with renal syndrome / 中华流行病学杂志

<p><b>OBJECTIVE</b>To evaluate the epidemiological and serological efficacy after 10 years of vaccination against hemorrhagic fever with renal syndrome (HFRS) vaccines in Zhejiang province.</p><p><b>METHODS</b>One county was randomly chosen as the research unit with all the healthy people between 16 and 60 years old were equally divided into study and control groups. The study group was vaccinated. Immunofluorescent antibody assay was used to test specific IgG antibody and Mcro-CPE method was used to test the titer of neutralizing antibody.</p><p><b>RESULTS</b>Two weeks after the full-course immunization, the seroconversion rate became 100% (67/67, with 95% CI as 96.3%-100%) by immunofluorescent antibody test (IgG) and 44.4% (8/18 with 95% CI as 22.0%-69.0%) by neutralization test with GMT titers as 72.1 and 4.6 respectively. Booster immunization was provided one year later. Time span as two weeks prior to, one year, one and half years, two years, three years and five years after booster immunization, the rates of seroconversion on immunofluorescent antibody using IFAT method, were 28.6%, 83.3%, 75.0%, 53.1%, 22.6%, 10.0% and 55.0% respectively, and rates of seroconversion of neutralizing antibody by Mcro-CPE method were 14.8%, 55.6%, 35.0%, 31.3%, 26.0%, 10.0% and 50.0% respectively. Nine years after the reinforcement, the rates of seroconversion of immunofluorescent antibody by IFAT method was only 7.1%. The vaccinated group had no patient seen but the control group appeared 34 patients including 3 deaths. According to the ten-year observation, the vaccine seemed effective with the protection rate in population reached 100%.</p><p><b>CONCLUSION</b>HFRS vaccine was effective on epidemiological, social and economical efficacy.</p>