BY NANCY S. LOVING, DVM
Birds are the reservoir for West Nile virus, meaning mosquitoes that bite an infected bird can then transmit the disease to horses and humans.
MAXFIELD WEAKLEY/SHUTTERSTOCK
It may seem as if West Nile virus has always been a threat to horses. However, it only arrived on the Northeastern shores of the United States just two decades ago in 1999. Within a short three-year period, the virus was found across the country in 15,000 horses in 41 states.