Falcone E, Cordioli P, Sala G, Tarantino M, Tollis M
Istituto Superiore di Sanità, Rome, Italy.
Vet Res Commun. 2001 Feb;25(2):161-7. doi: 10.1023/a:1006465120869.
Following the first official report of a clinically severe outbreak of bovine viral diarrhoea disease occurring in a farm in northern Italy, which had originated from the use of a live vaccine contaminated with a strain of BVD genotype II virus, a retrospective study on the prevalence of BVDV genotypes in Italy became highly relevant. For this purpose, the genotype of 78 BVDV-positive specimens, obtained in 1998-1999 from dairy cattle in an area near to where the outbreak occurred, was characterized by PCR technology. Two sets of primers, spanning the 5' UTR of BVDV genome, were used sequentially in a first round of RT-PCR, performed on viral RNA extracted directly from 15 clinical samples and 63 BVDV-infected cell-culture fluids; a second PCR assay followed to selectively amplify only BVDV genotype II. All the viruses under study were characterized as BVDV genotype I. As well as contributing to a better understanding of the prevalence of BVDV genotypes in the field, the results of the present study illustrate the possibility that novel BVDV strains can emerge in susceptible animals through the use of contaminated immunobiological products for bovine use.
在意大利北部一个农场首次官方报告发生临床上严重的牛病毒性腹泻疾病疫情后，该疫情源于使用了被一株牛病毒性腹泻病毒II型污染的活疫苗，对意大利牛病毒性腹泻病毒（BVDV）基因型的流行情况进行回顾性研究变得至关重要。为此，采用PCR技术对1998 - 1999年从疫情发生地附近地区的奶牛中获得的78份BVDV阳性样本的基因型进行了鉴定。在第一轮逆转录聚合酶链反应（RT-PCR）中，依次使用两组跨越BVDV基因组5'非翻译区（UTR）的引物，该反应是对直接从15份临床样本和63份BVDV感染的细胞培养液中提取的病毒RNA进行的；随后进行第二轮PCR检测，以选择性地仅扩增BVDV II型。所有研究的病毒均被鉴定为BVDV I型。本研究结果不仅有助于更好地了解该领域BVDV基因型的流行情况，还说明了通过使用受污染的牛用免疫生物制品，新的BVDV毒株可能在易感动物中出现的可能性。
