ENZYME-LINKED-IMMUNOSORBENT-ASSAY FOR SEROLOGICAL SURVEY OF EQUINE ARTERITIS VIRUS IN RACEHORSES

To examine antibodies against equine arteritis virus (EAV), an enzyme- linked immunosorbent assay (ELISA) using purified virus antigen was de veloped. The results of ELISA were compared with those of serum neutra lization (SN) tests. The ELISA absorbance values and the SN titers in sera collected weekly from EAV-infected horses showed a similar patter n. The ELISA could detect antibody to EAV in horses experimentally inf ected with not only a homologous virus strain, which was used as the E LISA antigen, but also a heterologous strain. Using the ELISA, serum s amples collected in 1996 from racehorses in three prefectures (Hokkaid o, Ibaraki, and Shiga) were examined and there was no evidence of rece nt EAV infection among these racehorse populations in Japan. The ELISA should be a simple and highly specific method for rapid screening of EAV infection in racehorses.