DETECTION OF ANTIBODIES TO BOVINE VIRAL DIARRHEA VIRUS (BVDV) AND CHARACTERIZATION OF GENOMES OF BVDV FROM BRAZIL

An ELISA for the detection of antibodies to bovine viral diarrhea viru s (BVDV) was developed based on antigens derived from a genotype I BVD V strain isolated in Switzerland. Using monoclonal antibodies we showe d that this antigen contained the conserved non-structural protein NS3 whereas it essentially lacked the more strain-specific E2 surface gly coprotein. This ELISA has a sensitivity of 97.5% and a specificity of 99.2% as compared to the serum neutralization test (SNT). Preliminary experiments showed that this ELISA reliably detects antibodies to BVDV strains circulating in Brazil. Serum samples obtained from 430 adult cattle on 19 farms of the State of Rio Grande do Sul (Brazil) and one farm from Corrientes (Argentina) were tested for antibodies by means o f this ELISA. We found antibodies in 56%+/-15.1% of the cattle sera te sted, which indicates that, in Brazil, the prevalence of infection wit h BVDV is similar to that found in Europe and the USA. Our sequence an alysis of two BVDV isolates showed that BVDV of both genotypes I and I I circulate in Brazil. (C) 1998 Elsevier Science B.V. All rights reser ved.