Florida Horse Contracts WNV
On Sept. 23, officials at the Florida Department of Agriculture and Consumer Services (FDACS) confirmed a Lake County horse with West Nile virus (WNV). The 5-year-old Quarter Horse gelding, whose vaccination status was not reported, began experiencing clinical signs, including ataxia (loss of muscle control) and mild muscle fasciculations (twitching), on Sept. 14. The horse is recovering.

This is Florida’s 10th confirmed equine case of WNV in 2020.

About West Nile Virus

WNV transmission occurs when infected mosquitoes feed on animals, as well as humans, after having fed on infected birds.

Clinical signs of WNV in horses include:

  • Mild anorexia and depression
  • Fine and coarse muscle and skin fasciculation;
  • Hyperesthesia (hypersensitivity to touch and sound);
  • Changes in mentation (mentality), when horses look like they’re daydreaming or “just not with it”;
  • Occasional drowsiness;
  • Propulsive walking (driving or pushing forward, often without control);
  • Spinal signs, including asymmetrical weakness; and
  • Asymmetrical or symmetrical ataxia.

West Nile virus has no cure; however, some horses can recover with supportive care. Equine mortality rates can reach 30-40%. The American Association of Equine Practitioners includes WNV as one of the core diseases all horses should be vaccinated against at least annually.