Comparative evaluation of liquid-phase blocking ELISA and solid-phase competition ELISA methods for the detection of antibodies to the structural proteins of foot-and-mouth disease types O and A viruses

In this study, we compared 2 methods, liquid-phase blocking ELISA (LPBE) and solid-phase competition ELISA (SPCE), for the detection of antibodies to the structural proteins of foot-and-mouth disease virus (FMDV). These methods were compared using sera collected from cattle (n = 30) without a history of foot-and-mouth disease infection or vaccination, cattle (n = 180) vaccinated with oil-adjuvanted bivalent vaccine, and international reference sera (positive, weak positive, and negative) for FMDV serotypes O and A. The results showed that SPCE had a better specificity (96.67% for serotype O and 100% for serotype A) than LPBE (90% for serotype O and 93.33% for serotype A). Sensitivity of LPBE (97.22% for serotype O and 98.33% for serotype A) was almost equivalent to that of SPCE (98.33% for serotype O and 98.89% for serotype A). It can be concluded that SPCE is more suitable than LPBE for use as a screening test for the detection of antibodies against structural proteins of FMDV.