Submitted to: Research in Veterinary Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 8/20/2013
Publication Date: 2/1/2014
Publication URL: http://handle.nal.usda.gov/10113/61243
Citation: Pecora, A., Malacari, D.A., Ridpath, J.F., Perezaguirreburualde, M.S., Combessies, G., Odeon, A., Romera, A.S., Golemba, M., Wigdorovitz, A. 2014. First finding of genetic and antigenic diversity in 1b-BVDV isolates from Argentina . Research in Veterinary Science. 96(1):204-212. DOI: 10.1016/j.rvsc.2013.11.004. Interpretive Summary: Bovine viral diarrhea viruses (BVDV) are a group of viruses that infect dairy and beef cattle worldwide. Infection results in significant losses to producers. There is a lot of variation among BVDV. Based on these variations BVDV can be placed into different groups. These groups are called genotypes. Different BVDV genotypes are found in different geographic regions. In this paper the authors look at the genotypes of BVDV found in Argentina. The significance of this research is that the genotype of BVDV that predominates in Argentina is different than the genotype of BVDV found in vaccines that are marketed in that country. The authors of the paper present data that suggests that animals vaccinated with the available vaccines may not be fully protected against infection with the viruses that are circulating in Argentina.
Technical Abstract: Infection with Bovine Viral Diarrhoea Viruses (BVDV), which belongs to the pestivirus genus of the family Flaviviridae, results in significant economic losses for cattle producers. BVDV infection of cattle results in a wide range of clinical manifestations, ranging from mild respiratory disease to fetal death and mucosal disease, depending on the virulence of the virus and the immune and reproductive status of the host. BVDV has been classified into two species, BVDV 1 and BVDV 2, each of which can be divided into subgenotypes. Antigenic differences correlating to genetic differences was demonstrated by several studies including cross neutralisation using polyclonal sera, monoclonal antibody binding and response of BVDV persistently infected animals to vaccination. In this study 30 BVDV isolated from samples collected in ¨Region Pampeana" were characterised by phylogenetic analysis. The isolates were genotyped based on comparison of the 5´untranslated region (5' UTR) and the E2 gene (which codes for the major envelope glycoprotein). In both phylogenetic trees 27 of the isolates were classified as BVDV 1 and were assigned to 2 different subgenotypes BVDV 1a (4/30), and BVDV 1b (23/30). The remaining 3 isolates were typed as BVDV 2a (2/30) and BVDV 2b (1/30). Eight of the BVDV 1b isolates were further characterised by crossneutralisation tests using guinea pig monospecific antisera and sera from bovines vaccinated with two different commercial vaccines. The results demonstrated the presence of a marked antigenic diversity among Argentinean BVDV isolates and suggest the need to incorporate BVDV 1b isolates in diagnostic and immunisation strategies.