Retrospective epidemiological evaluation of molecular and animal husbandry data within the bovine viral diarrhoea virus (BVDV) control programme in Western Austria during 2009-2014.

A retrospective epidemiological investigation of molecular and animal husbandry data collected over an observation period of five years (2009-2014) within the compulsory bovine viral diarrhoea virus (BVDV) control programme in Western Austria, covering the federal provinces of Tyrol and Vorarlberg is presented in this study. Samples collected from 232 infected calves were phylogenetically classified based on the 5' untranslated region (5'UTR). All but 13 samples, which were typed as border disease virus subtype 3 (BDV-3), belonged to the bovine viral diarrhoea virus genotype 1 (BVDV-1) and clustered within six different subtypes (1b, 1e, 1f, 1h, 1d and 1k). Movement data and survival times from infected individual animals were analysed because of their potential of passing on infection to naive herds. From the moment of submission of the laboratory results, 180 animals were culled within the first month, 13 lived longer than two but not longer than six months and seven infected animals lived longer than one year. 13 of the infected animals were born on alpine pastures and eleven infected animals were grazed on mountain pastures during summer. The movement of infected animals and the role of trade in alpine areas are a possible source for spreading the infection, thus hampering the progress of eradication.