Infezione da Ovine Herpesvirus tipo 2 in allevamenti ovini in Umbria
Ovine gammaherpesvirus 2 (OvHV-2) is a gammaherpesvirus that causes an asymptomatic infection in sheep and a severe systemic disease in other ruminants and pigs, called malignant catarrhal fever (FCM). The control of the infection in sheep is the key to avoid the FCM. Moreover, a role of this virus in the pathology of the sheep can not be excluded. Aim of the present study was to investigate the presence of OvHV-2 in sheep flocks of the Umbria Region and understand the role of some characteristics of the farms for the infection. Nasal swabs of 39 sheep and 11 goats coming from 9 different farms were investigated for the presence of the OvHV-2 DNA by nested PCR. Twenty-nine out of 39 (74.4%) sheep and 3 out of 11 (27.3%) goats were positive. The role of the species, the age of the animals, the productive attitude, the breeding mixed with cattle and/or goats, and the effect of the single farm were evaluated as risk factors for the infection by univariable and multivariable statistical analysis. All these factors resulted significant by univariable analysis, whereas only the effect of the single farm remained significant in the multivariable analysis. Probably the farm contains other variables that are able to explain variation in the prevalence of OvHV-2. Further factors specific of each farm will have to be investigated to understand the epidemiology of the infection.