Skip to main content

Horse dies from rare virus, a sign mosquitos in MN are carrying it

EEE is a rare virus spread by mosquitos that can infect humans.

A horse in Aitkin County died after contracting a disease that is spread by mosquitos, indicating that mosquitos carrying Eastern equine encephalitis (EEE) are in the area and could also infect people.

The 7-year-old crossbred gelding horse was confirmed to have EEE last week, and before it died it was staggering, had impaired vision and was excessively drooling - all clinical signs of neurological disease, the Minnesota Board of Animal Health said in a news release Thursday.

The horse, who had no history of travel over the past three months, tested negative for other diseases, including rabies, West Nile virus encephalitis and Western equine encephalitis, the release noted. It was last vaccinated for EEE 18 months ago.

“The diseases EEE, WEE, and WNV in horses can be limited through vaccination protocols and decreased exposure to mosquitoes,” Board Senior Veterinarian Dr. Brian Hoefs said in a news release Thursday. “While COVID-19 has restricted many equine related activities, it is imperative to be vigilant about annual preventative care, including core vaccinations. We encourage all horse owners to work with their veterinarians to develop strategies for preventing EEE/WEE/WNV exposure and illness in their horses.”

On the property where the horse lives there are at least 11 other horses, who all appear healthy and have since received initial vaccinations for EEE/WEE/WNV with boosters pending, the release said. 

EEE can cause fatal infections in horses, with EEE being fatal in more than 90% of cases. Clinical signs of the virus include fever, lethargy, not eating and walking aimlessly.

EEE and people

EEE, which is primarily transmitted by mosquitoes, can also cause fatal infections in people. (Horses and people are "dead-end hosts," meaning they can't transmit the disease to other horses or people.)

The state animal board says cases of EEE involving horses are a "clear indication" that mosquitos infected with the virus are in the area and can infect humans.

According to the Mayo Clinic, EEE is a rare virus that can cause swelling of the brain, with symptoms typically starting 4-10 days after being bitten by an infected mosquito. Symptoms may include headache, fever, chills and vomiting. Signs and symptoms can worsen to disorientation, seizures and coma and lead to brain damage or, in some cases, death.

The only way to lower your chance of getting EEE is to prevent mosquito bites, especially if you spend time outdoors and in the woods, Mayo says. 

Mayo suggests using bug spray with DEET or picaridin, wearing long pants and long-sleeved shirts when outside, emptying standing water from outdoor containers, having screens on windows and doors, and using permethrin to treat clothing as ways to prevent mosquito bites.

Next Up

Screen Shot 2022-11-23 at 5.01.34 PM

Suspected Bloomington restaurant killer arrested in Oklahoma

The 47-year-old Texas man was arrested around 12:30 a.m. Thursday.

Screen Shot 2022-11-24 at 9.16.39 AM

Minnetonka woman, 23, ID'd as victim killed in Minneapolis crash

The fatal crash happened near the Minneapolis Convention Center on Nov. 21.


More than 100 geese, ducks found dead on partially frozen MN lake

The discovery was made in Waseca at the weekend.


After losing sponsor, advocates fear Minneapolis' Nice Ride could shut down

They are calling on the city to provide financial support till a new sponsor is found.

Screen Shot 2022-11-23 at 3.32.46 PM

Colleen Lindstrom announces departure from MyTalk radio show

Lindstrom's last broadcast on the long-running show will be Dec. 9.


Diocese of Superior identifies 23 clergy members with 'substantiated' abuse

The announcement from the diocese came after a multiple reviews with external agencies.


Flu surge worsens in schools ahead of Thanksgiving holiday

Earlier this week, Minnesota hospital leaders said the number of sick children is creating a capacity crisis for the health system.


Bloomington police investigating shooting; public asked to avoid area

This is a developing story. Please check back for updates.


Gallery: Modernist home on Duluth's observation hill listed for nearly $1.6M

The private hillside home offers sweeping views of the city.


Flickr - mosquito skin - Jim STauffer

Mosquito levels remain low - but there's some bad news

Get ready to learn about Culex mosquitoes and West Nile Virus.

police lights

Horse fatally shot in rural Otter Tail County

The animal was in a pasture with other horses when it was shot.

Deadly mosquito-borne virus found in northeastern Minnesota

The Eastern Equine Encephalitis Virus had not been found in Minnesota until recently. The virus can be fatal to humans, as well as wildlife. Its mortality leads one veterinarian to call it "the evil twin sister of West Nile Virus." Officials are studying whether the virus might be related to the disappearance of moose from the region.

White tail deer

Virus from midges has been causing deer deaths in Minnesota

Two deaths have been confirmed, and several more are suspected.

heart monitor, hospital

25 cases of rare child disease possibly linked to COVID-19 in MN

It's extremely rare, but health officials want parents to be aware.

Ticks are spreading more diseases every year in Minnesota

More than 26,000 tick-borne disease cases in Minnesota since 2004.


Woman dies after being dragged by horse in west-central MN

The 47-year-old from South Fargo died at the scene.