Development of an Indirect ELISA for detection of antibodies against Porcine Epidemic Diarrhea Virus in swine colostrums

Abstract

An Indirect ELISA PEDV KU1 was developed to detect the antibodies of porcine epidemic diarrhea virus (PEDV) in colostrum sample from pigs. The viral antigen was prepared from PEDV of TRUNG 1/38 strain outbreak in Thailand. The optimal antigen concentrations were tested with standard antibodies specific for Immunoglobulin G and Immunoglobulin A by checkerboard titration, selected at 1:320 and 1:40 dilution.  A total of 200 colostrum samples from non-infected farm (n=100) and 2-3 weeks of post infected farm (n=100) were tested for set a cut-off point by a two-graph receiver operating characteristics analysis, the result showed of broth antibodies provided a cut-off point at ≥ 0.4 = positive. This assay was validated by comparison with an indirect Immunofluorescence assay, the result of IgG antibodies showed that sensitivity = 90.56, specificity = 100% and kappa value at 0.905 and IgA antibodies provided sensitivity at 87.96%, specificity = 100% and kappa value at 0.879. These results indicated that the PEDV ELISA KU1 may be useful for detecting of both antibodies replaced on IFA. It is an alternative to be used to assess the disease situation.