Evidence of extensive renewed Schmallenberg virus circulation in Belgium during summer of 2016 - increase in arthrogryposis-hydranencephaly cases expected.

A seroprevalence study carried out between June and September 2016 in the Belgian sheep population showed a significant increase in overall (from 25% to 62%) and between-herd (from 60% to 96%) seroprevalence against Schmallenberg virus ( SBV) during this period, indicating the most extensive recirculation of SBV since its original emergence in 2011. SBV recirculation was confirmed by the detection of SBV RNA-positive Culicoides obsoletus complex midges collected in the region of Antwerp in August 2016, reaching a minimum infection rate of 3%. The recirculation of SBV in the largely unprotected ruminant population during summer 2016 will likely cause an increase in the number of arthrogryposis-hydranencephaly cases in newborn ruminants during the coming months. [ABSTRACT FROM AUTHOR]