West Nile Virus Detected in Michigan Horse

The Michigan Department of Agriculture and Rural Development (MDARD) has confirmed Michigan’s first West Nile virus (WNV) case in a domestic animal in 2026. The case involves a three-year-old horse in Missaukee County in north-central Michigan. The horse is currently responding to treatment and is believed to be unvaccinated.

This case is not in Van Buren or Cass counties, but mosquitoes that carry WNV, eastern equine encephalitis (EEE), and other mosquito-borne diseases can remain active across Michigan until there has been a hard freeze, when temperatures fall below 28°F.

Protect yourself and your animals

Residents can take steps to reduce mosquito exposure:

• Remove standing water around your home and property.
• Keep livestock in a barn with fans during peak mosquito activity, from dusk to dawn.
• Use an insect repellent on animals that is approved for their species.
• Talk with your veterinarian about vaccinating horses against WNV and other mosquito-borne diseases.

Contact a veterinarian if a horse develops signs of illness, including mild fever, stumbling, difficulty standing or being unable to stand.

WNV is spread through the bite of an infected mosquito. It is not spread through horse-to-horse or horse-to-human contact. Cases are most commonly seen in Michigan during late summer and early fall.

If a Michigan animal is suspected of having WNV, funding may be available through an arbovirus grant to help cover testing costs. Contact MDARD at 800-292-3939 for more information.

Learn More

For additional information about West Nile virus and other mosquito-borne diseases, visit:

Michigan Emerging Diseases — MDARD

Continue taking precautions against mosquito bites until a hard freeze occurs.