ELISA METHOD FOR DETECTION OF INFLUENZA-A INFECTION IN SWINE

An antigen-capture enzyme-linked immunosorbent assay (ELISA) was devel oped to monitor virus shedding associated with experimental infection with a field strain of swine influenza in pigs. The assay consisted of a monoclonal anti-nucleoprotein capture antibody and a biotinylated r abbit anti-influenza A (H1N1) sandwich antibody. The antigen-capture s ystem was capable of detecting as little as 1 ng/ml purified vints. Th e ELISA system surpassed egg cultivation procedures in the detection o f low levels of shedding virus. Egg cultivation procedures indicated t hat most viral shedding had ceased by day 10 postinfection. In contras t, antigen-capture ELISA still showed an ongoing presence of viral ant igen. A virus-capture ELISA, using this capture-sandwich antibody syst em, is equivalent in sensitivity to conventional egg inoculation proce dures for the detection of the early phases of virus shedding. The aut omative potential of an ELISA-based system coupled with a substantiall y reduced assay time requirement give this virus-capture ELISA a disti nct advantage over other cell culture or egg-based diagnostic techniqu es.