BROOMFIELD, Colo. (AP) -- Veterinarians at Colorado State University have diagnosed a horse in Weld County with West Nile Virus, the first equine case recorded this year.
State Department of Agriculture officials say the transmission of the disease varies from year to year and depends on a number of factors, including the number of mosquitoes. Infected horses can display symptoms that include head tilt, muscle tremors, stumbling, lack of coordination, weakness of the limbs or partial paralysis.
West Nile Virus can be carried by birds and then spread by mosquitoes that bite those birds. The mosquitoes can then pass the virus to humans and animals.
Vaccines are effective in preventing the spread, as can getting rid of stagnant water sources where mosquitoes breed.