Wadena County horse recovering after testing positive for West Nile virus

A horse in Wadena County, Minnesota tested positive for West Nile virus, the state board of animal health reported Monday.

According to the board, a 3-year-old Quarter Horse filly tested positive for the virus last week. A veterinarian was called to examine the horse on Aug. 19 because it was unable to stand on its rear legs. The horse did not have an elevated temperature and was eating and drinking while down. The veterinarian decided to collect samples for WNV testing and provided supportive care to the horse.

On Aug. 26, they received test results confirming a WNV diagnosis. According to the board, the affected horse was not current on WNV vaccinations. An additional 15 horses reside on site, and those not current on WNV vaccinations are being given boosters.

Dr. Brian Hoefs, Senior Veterinarian of the Equine Program, said in a release that the horse appears to be recovering. 

"Horse owners should work with their veterinarian on a routine vaccination program to reduce the risk of these preventable diseases and increase the animal’s chances of recovering fully if they’re infected," Dr. Hoefs said in the release.

According to the Minnesota Board of Animal Health, West Nile virus is regularly found in the U.S., and birds serve as the primary host of the disease. The virus circulates between infected birds and mosquitoes. Once infected, the mosquitoes can transmit the virus to horses or people. The virus can cause encephalitis, an inflammation of the brain and spinal cord. Infected horses may or may not show neurological symptoms and may recover completely, especially those who have a history of annual vaccination.

Vaccines for horses are widely available and have been proven to be effective in preventing infection. The following steps can also be taken to reduce risks:

  • Change water in drinking troughs every week.
  • Mow long grass
  • Drain stagnant water puddles
  • Remove items mosquitoes use for breeding grounds, like old tires and tin cans
  • Place and maintain screens over windows and stable doors
  • Use mosquito repellents to protect horses and people from mosquito bites

This is a high-risk time of year for West Nile virus transmission. Non-negative test results for West Nile virus disease must be reported to the Board of Animal Health.