OKLAHOMA CITY (AP) - Horse owners in Oklahoma are being encouraged to vaccinate their animals against West Nile virus and Eastern equine encephalitis.
The Oklahoma Department of Agriculture, Food and Forestry has reported about 40 cases of each disease in the past two years.
Both diseases are carried by birds and transmitted to mosquitoes, which can spread the viruses to humans and horses.
Equine vaccinations are available, but vaccines for humans have not yet been created.
The risk for contracting the viruses is higher in areas where mosquitoes lay their eggs, including near standing water.