A mosquito-borne virus spreading into parts of Western Canada is raising concerns among livestock specialists who warn it could disrupt sheep breeding programs if it gains a foothold in local flocks. The disease, known as Cache Valley virus, has been detected in mosquito populations in neighbouring U.S. states and has historically caused reproductive losses in sheep, particularly during early gestation.

Researchers monitoring its movement say warming temperatures and changing insect patterns are increasing the likelihood of transmission in regions that previously faced minimal risk. The virus does not typically produce noticeable symptoms in adult animals, but it can lead to severe congenital defects or pregnancy losses, creating major challenges for producers who rely on tight breeding schedules and consistent lambing outcomes.

Alberta sheep producers are being advised to watch for abnormal birth patterns and to stay connected with veterinary networks as surveillance efforts continue. While no widespread outbreaks have been confirmed in Canada, specialists note that the arrival of other vector-borne livestock diseases in recent years demonstrates how quickly conditions can shift.

Veterinary organizations and livestock health authorities are reviewing mitigation strategies as they track the virus’s progression through North America. Continued monitoring, along with awareness among breeders, is expected to play a key role in reducing potential losses should the virus enter Canadian flocks.