title: Increased genetic diversity of BVDV-1: recent findings and implications thereof.
abstract: Sequence-based genotyping was recently used to distinguish between the BVDV-1 and BVDV-2 species of the bovine viral diarrhoea virus (BVDV). Quite recently, a new putative species, BVDV-3, was also detected. The phylogenetic analysis of the 5'-untranslated region (UTR) and Npro region has revealed at least 17 distinct subtypes for BVDV-1 to date. The aim of this study was to further investigate the genetic heterogeneity of BVDV-1 in Italy, by analysing 173 virus sequences from isolates collected over an 18-year period (1997-2014). Viral RNA was extracted from the original biological samples identified as BVDV-1-positive. Reverse transcription (RT) and polymerase chain reaction (PCR) assays targeting a 288-base pair (bp) region of the 5'-UTR and a 428-bp region encoding the autoprotease Npro were performed, and the RT-PCR products were sequenced. The phylogenetic analysis of the 5'-UTR and Npro sequences re-confirmed the circulation of ten out of eleven subtypes previously discovered in Italy. Interestingly, four isolates differed significantly from all of the bovine pestiviruses identified so far, thereby providing evidence for the circulation of three novel subtypes that have not been documented so far. The growing number of reports on BVDV-1 heterogeneity, including the recent findings reported herein, raises concern related to the emergence and spread of new BVDV variants, with possible implications for animal health and disease control. This global issue needs to be addressed with the highest priority.
authors.affiliation: Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, via Salvemini 1, 06126, Perugia, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Giammarioli
authors.forename: Letizia
authors.initials: L
authors.lastname: Ceglie
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Rossi
authors.forename: Moira
authors.initials: M
authors.lastname: Bazzucchi
authors.forename: Cristina
authors.initials: C
authors.lastname: Casciari
authors.forename: Stefano
authors.initials: S
authors.lastname: Petrini
authors.forename: Gian Mario
authors.initials: GM
authors.lastname: De Mia
mesh_terms: D020121:5' Untranslated Regions / Q000235:genetics; D000818:Animals; D002417:Cattle; D016000:Cluster Analysis; D030241:Diarrhea Virus 1, Bovine Viral / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D014644:Genetic Variation; D005838:Genotype; D007558:Italy; D008969:Molecular Sequence Data; D018182:Pestivirus Infections / Q000662:veterinary / Q000821:virology*; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D014764:Viral Proteins / Q000235:genetics
chemical_list: D020121:5' Untranslated Regions; C507353:Npro protein, bovine viral diarrhea virus; D012367:RNA, Viral; D014764:Viral Proteins