Genetic characterization of border disease virus (BDV) isolates from small ruminants in Italy

Abstract

Border disease virus (BDV) belongs to the Pestivirus genus in the family Flaviviridae. Genetic analyses of pestiviruses that have been isolated from sheep and goat have led to the proposal that BDV isolates can be phylogenetically segregated into at least seven clusters, subtypes BDV-1 to BDV-7. In order to investigate the genetic heterogeneity of small ruminant pestivirus isolates in Italy, a selection of 5'-UTR sequences from isolates that were collected from clinical specimens between 2002 and 2014 was analysed. Phylogenetic reconstructions indicated that the BDV-positive samples clustered within the BDV-1, BDV-3, BDV-5, and BDV-7 groups. These results suggested high genetic diversity within the Italian BDV field isolates. The phylogenetic analysis indicated the first evidence of BDV-1 and BDV-5 circulation in Italy. The marked diversity of the pestivirus isolates might reflect the sheep trade with foreign countries.

Evidence for Tunisian-Like Pestiviruses Presence in Small Ruminants in Italy Since 2007

“…No correlation was observed between pestiviruses isolated from sheep and goats in this study and strains previously isolated from small ruminants in Italy and classified into different subtypes of the BDV genotype (Rosamilia et al, 2014;Giammarioli et al, 2015b).…”

“…However, from an epidemiological point of view, the finding of similar viruses in both sheep and goats is not surprising as other pestiviruses have been frequently isolated from both sheep and goats, such as Turkey isolates (Postel et al., ) and BDV (Giammarioli et al., ; Mao et al., ).…”

Detection of border disease virus in Mexican cattle

“…The ORF encodes a polyprotein cleaved into 12 proteins arranged in the following order: N pro , C, E rns , E1, E2, p7, NS2/3, NS4A, NS4B, NS5A and NS5B. The 5′UTR has been used for genetic classification of new BDV isolates into genotypes and subgenotypes (Giammarioli et al., ). Because the 5′UTR is highly conserved among pestiviruses, the comparison of the sequences from this region is widely accepted for phylogenetic analyses; those analyses have led to the segregation of BDV isolates into at least eight subgenotypes, BDV‐1 to BDV‐8 (Peletto et al., ).…”

“…BDV‐2 is made up of viruses isolated from Germany (Becher et al., ). Similarly, BDV‐3 includes isolates from France (Dubois, Russo, Prigent, & Thiery, ), Austria (Krametter‐Froetscher et al., ), Switzerland (Stalder et al., ), China (Mao et al., ), India (Mishra et al., ) and Italy (Giammarioli et al., ). BDV‐4 comprises a virus isolated from Pyrenean chamois (Arnal et al., ).…”

“…BDV‐6 had been detected in France (Dubois et al., ). BDV‐7 includes goats and sheep pestivirus from Italy (Giammarioli et al., ; Peletto et al., ). And BDV‐8 comprises strains isolated from cattle, sheep and goats in Switzerland (Peterhans, Bachofen, Stalder, & Schweizer, ) and from a goat kid in Italy (Peletto et al., ).…”