Akabane Virus and Schmallenberg Virus
Akabane virus and Schmallenberg virus are closely related viruses of the genus Orthobunyavirus and infect predominantly ruminants. They are able to cross the placenta and cause abortion, premature birth or severe fetal malformation (arthrogryposis-hydranencephaly syndrome), when naïve pregnant animals are infected during a critical phase of gestation. Akabane virus circulates in Africa, the Middle East, Asia, and Australia, while Schmallenberg virus is endemic on the European continent. Both viruses are transmitted between their mammalian hosts by biting midges of the genus Culicoides. For disease prevention, inactivated Akabane and Schmallenberg vaccines are commercially available.