Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: March 29, 2001
Publication Date: N/A
Technical Abstract: Variability among bovine viral diarrhea viruses (BVDV) impacts detection. Classification based on phylogenetic analysis divides BVDV strains into two genotypes, BVDV1 and BVDV2. Biologically important differences are seen between the two genotypes. In North America, the BVDV1 genotype can be further subdivided into the BVDV1a and BVDV1b subgenotypes. The practical significance of this subdivision is not known, however BVDV1b strains have evaded BVDV1a vaccines. Genomic differences can be exploited for differentiation of genotype via polymerase chain reaction (PCR). Differences are seen throughout the genome. Many different regions have been used for differential PCR, but tests based on conserved regions are more likely to pick up out lying variants. Using PCR for primary detection has practical limitations. Antibody (Ab) based techniques can be used. However, caution is advised when using these techniques because of the variability observed among BVDV isolates within genotypes. This is particularly true of tests based on Ab prepared against the E2 viral polypeptide. Direct sequence comparison, while impractical for routine detection, is an indispensable tool for epidemiology and for identification and characterization of new pestivirus genotypes and subgenotypes.