A new enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies against foot-and-mouth disease virus. II. Application.

The liquid-phase blocking sandwich ELISA has been evaluated for the serological study of antibodies against foot-and-mouth disease virus (FMDV). The titres recorded for sera from a population of more than 300 British uninfected, unvaccinated cattle which were examined against each of the seven immunologically distinct FMDV types were less than 1 in 40. A positive correlation between ELISA and VN titres was recorded for sera either vaccinated or involved in outbreaks of FMDV. The overall regression between the ELISA/VN data showed that 1 in 16 by VN was equivalent to 1 in 40 by ELISA. Thus ELISA is sensitive, specific and reproducible and results may be directly correlated to those recorded by VN. Serum titres may be interpreted as positive or negative and the number of sera which require retesting would be considerably less than by VN. It is suggested that this ELISA may be used as an alternative to the existing VN test for the quantification of antibodies against FMD virus.