Epidemiological pattern and risk factors associated with bovine viral-diarrhoea virus (BVDV) infection in a non-vaccinated dairy-cattle population from the Asturias region of Spain

Genetic typing of bovine viral diarrhoea virus in cattle on Irish farms

“…PI cattle play a major role in the maintenance and transmission of virus (Houe 1999;Lindberg 2002;MainarJaime et al 2001).. The most efficient method of transmission for BVDV is direct transmission between PI animals and seronegative animals as PI (Houe 1999;Lindberg 2002;Mainar-Jaime et al 2001). The source of infection also plays a role in the rate of transmission as a TI animal will shed considerable lower levels of virus in comparison to a PI animal leading to a slower progression within the herd.…”

“…The age and gender profile of the group will be an important factor as the presence of an infected animal in a group of pregnant females may lead to the development of PI calves. Thus, maintaining a constant source of BVDV within the herd (Houe 1999;Lindberg 2002;Mainar-Jaime et al 2001).…”

“…Finally, animals developing severe nasal discharge and/or coughing can lead to the contamination of feed, forage, water sources, feeding equipment, bedding material and the general environment with virus laden secretions which promotes the spread of the virus. Coughing can also result in the virus becoming airborne contributing to the transmission into adjoining holding areas or paddocks (Lindberg 2002;Mainar-Jaime et al 2001).…”

“…cattle, (Mainar-Jaime et al 2001), pigs (Tao et al 2013), sheep (Paton et al 1995), deer (Becher et al 1999;Harasawa 2000), alpaca (Kim et al 2009) and camels (Gao et al 2013).…”

Infectious Agents

“…34 Similar rates of seroprevalence have been detected in cattle herds worldwide, but the observed range varied widely among countries (13-90%) and was largely influenced by the examined population, potentially reflecting global differences in cattle management. [36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52] In contrast to seroprevalence rates, the prevalence of PI cattle is considerably lower and is generally believed to be less than 1% of all cattle. Persistently infected cattle may be found in clusters within groups of cattle, elevating the prevalence within populations.…”