A Review on Reliable and Standardized Animal Models to Study the Pathogenesis of Schmallenberg Virus in Ruminant Natural Host Species.

In the late summer of 2011, the Netherlands reported a cluster of reduced milk yield, fever, and diarrhea in dairy cattle. In March 2012, congenital malformations appeared, and Schmallenberg virus (SBV) was identified, becoming one of the few orthobunyaviruses distributed in Europe. Initially, little was known about the pathogenesis and epidemiology of these viruses in the European context, so assumptions were largely extrapolated from related viruses and other regions worldwide. To study SBV's pathogenesis and its ability to cross the placental barrier, standardized and repeatable models that mimic clinical signs observed in the field are essential. This review discusses some of the latest experimental designs for infectious disease challenges involving SBV, covering infectious doses, routes of infection, inoculum preparation, and origin. Special attention is given to the placental crossing associated with SBV.