an infectious disease of sheep caused by intrauterine infection with a togavirus closely related to the bovine virus diarrhoea virus. The congenital signs that identify the presence of the disease are an abnormally hairy birth coat, gross tremor of skeletal muscle, poor growth, a variety of skeletal deformities and defective myelination in the central nervous system, flaviviiruse põhjustatud haigus, mis tekitab vastsündinud talledel lihaste tõmblusi, toonilis-kloonilisi krampe ja villa pulstumist