Exposure to Schmallenberg virus in Irish sheep in 2013

Fetal malformation due to Schmallenberg virus (SBV) was diagnosed in 49 cattle herds and 30 sheep flocks in the south and south east of Ireland in 2013. Serological and pathological studies in cattle, and pathological studies in sheep indicated SBV exposure was confined to the south and south east of Ireland. It was anticipated that SBV exposure would spread north westwards over the course of the 2013 vector season. The objectives of this study were to determine the geographic distribution of SBV exposure in Irish sheep before and during the 2013 vector season, and to determine if SBV was active in flocks where SBV infection had been previously confirmed. There was no further increase in the geographic extent of exposure to SBV during the course of 2013, nor was there evidence of SBV transmission during 2013 in flocks where SBV had been previously confirmed.