The study was aimed at establishing an indirect ELISA for epidemiological investigation of hepatitis E viral(HEV) infection in pigs from the major pig-producing regions of Zhejiang Province. The gene fragment covering...The study was aimed at establishing an indirect ELISA for epidemiological investigation of hepatitis E viral(HEV) infection in pigs from the major pig-producing regions of Zhejiang Province. The gene fragment covering the immunogenic epitopes of HEV ORF2 was synthesized and expressed in Escherichia coli.Western blot analysis revealed that the purified protein reacted to HEV positive sera,but not to positive sera from some other common viruses that infect pigs.An indirect ELISA system was then developed using truncated HEV ORF2 protein as the coating antigen and had diagnostic accuracy of 91.5% as compared with a diagnostic kit for HEV antibodies.A total of 1 330 serum samples were collected from 46 pig farms in Zhejiang Province from 2005-2008 and tested for sero-prevalence of HEV using the indirect ELISA.The average HEV-positive rate was 55.7%(741/1 330).The positive rate of 2005 and 2006 was 62.7%(175/279) and 61.4%(301/490) respectively,much higher than those of 2007(43.0%,59/137) and 2008(48.6%,206/424).Pigs aged 66-100 days had a statistically higher positive rate(58.2%,110/189) when compared to that of pigs aged 30-65 days(39.7%,73/184) or 101-160 days(44.1%,83/188).Only three herds in the study were HEV antibody-negative,indicating high sero-prevalence of HEV in the pig populations in Zhejiang Province.展开更多
基金supported by Technological Project of Zhejiang Emtry-Exit Inspection and Quarantine Bureau(ZK200611)Technology Innovation Service Platform of Inspection and Quarantine for Safe Frontier (2006C1704)
文摘The study was aimed at establishing an indirect ELISA for epidemiological investigation of hepatitis E viral(HEV) infection in pigs from the major pig-producing regions of Zhejiang Province. The gene fragment covering the immunogenic epitopes of HEV ORF2 was synthesized and expressed in Escherichia coli.Western blot analysis revealed that the purified protein reacted to HEV positive sera,but not to positive sera from some other common viruses that infect pigs.An indirect ELISA system was then developed using truncated HEV ORF2 protein as the coating antigen and had diagnostic accuracy of 91.5% as compared with a diagnostic kit for HEV antibodies.A total of 1 330 serum samples were collected from 46 pig farms in Zhejiang Province from 2005-2008 and tested for sero-prevalence of HEV using the indirect ELISA.The average HEV-positive rate was 55.7%(741/1 330).The positive rate of 2005 and 2006 was 62.7%(175/279) and 61.4%(301/490) respectively,much higher than those of 2007(43.0%,59/137) and 2008(48.6%,206/424).Pigs aged 66-100 days had a statistically higher positive rate(58.2%,110/189) when compared to that of pigs aged 30-65 days(39.7%,73/184) or 101-160 days(44.1%,83/188).Only three herds in the study were HEV antibody-negative,indicating high sero-prevalence of HEV in the pig populations in Zhejiang Province.
