Lakewood, Colo. (AP) - Colorado agriculture officials say at least seven cases of West Nile virus have been diagnosed in horses so far this year.
State Veterinarian Keith Roehr says there was only one reported equine case of West Nile virus in Colorado last year.
The latest positive tests were submitted from horses examined in North Central, Northeast and Southeast Colorado.
The virus is carried by mosquitoes and can cause an inflammation of the brain and spinal cord. Symptoms in horses include head tilt, muscle tremors, stumbling, lack of coordination, weakness of the limbs or partial paralysis.
As of Aug. 21, state health officials were reporting 14 verified human cases of the virus in Colorado.
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