Detection of FMD virus antigens and antibodies using staph protein-a rapid agglutination test in comparison with the used traditional methods

Abstract

Considering rapid accurate detection of FMD virus antigens and antibodies is an essential corner stone in the epidemiological studies; Staphylococcal protein-A (SPA) was successfully prepared and used for application of rapid agglutination test (RAT) on both of processed infected tongue epithelium and infected cell culture fluid for detection of FMD virus antigens using reference viruses and anti-sera. It was found that the traditional virus neutralization test (VNT) consuming long time (18-24 hours) and RAT with the shortest time (2-5 minutes) were able to detect the antigens of FMDV type O; A and SAT2 with titer ranged from ≤ log10 up to 7log10 TCID50/ml. In addition, RAT carried on serum samples obtained from vaccinated animals revealed positive results with titers similar to those obtained by serum neutralization test (SNT) ranged from ≤ 2 up to 256 for the three virus types with shorter time (2-5 minutes) than that consumed by SNT (18-24 hours). It was noticed that high antigen or antibody titers showed strong agglutination while weak agglutination was noticed with lower titers. So it could be concluded that the present work provides a rapid; sensitive and accurate test to detect FMDV antigens and antibodies as safe; easy to be used, highly sensitive, rapid field test, of low cost and having friendly environmental relationship. Key word: Foot and mouth disease (FMD); Staph protein A (SPA); Rapid agglutination test (RAT).