Officials reported seven cases of WNV in Wyoming horses residing in Campbell, Fremont, Goshen, Park, and Sheridan counties.

So far this year positive WNV cases have been identified in Kern, Merced, Placer, Sacramento (two cases), Shasta, and Stanislaus counties, California animal health officials said.

Both horses–one from Cattaraugus County and one from Genesee County–were euthanized.

Animal health officials have confirmed cases in Ashtabula, Champaign, and Geauga counties. Two horses are recovering and one was euthanized.

Officials confirmed three cases in Park County and one in Sheridan County.

The affected 16-year-old pony mare was euthanized.

An unvaccinated 2-year-old Quarter Horse filly showed an onset of clinical signs on Aug. 27, including facial and muscle fasciculations (twitching) and Grade 2/5 ataxia (incoordination) in all four limbs.

The unvaccinated 6-year-old Tennessee Walking Horse stallion from Lewis County was euthanized after becoming recumbent.

One infected horse in Anne Arundel County responded to supportive treatment and recovered, but the affected Carroll County horse had severe neurologic clinical signs was euthanized. Neither was vaccinated against WNV.

The Delaware state veterinarian has confirmed two cases of West Nile virus (WNV) in horses in Kent County.

A 10-year-old Quarter Horse stallion, with an unknown vaccination history, from Jerome County developed neurologic signs of disease and was subsequently euthanized.

A 2-year-old Quarter Horse mare from Polk County was euthanized Aug. 25 due to disease severity.

Horses from Holmes, Medina, and Tuscarawas counties have tested positive for West Nile virus thus far in 2018.