An especially severe outbreak of a highly contagious equine virus has led to voluntary quarantines and elaborate precautions to protect horses in Minnesota and surrounding states.

Nowhere are the restrictions more visible than at this year's Minnesota Horse Expo, a popular event now in its 32nd year that runs Friday through Sunday at the Minnesota State Fairgrounds.

Only 50 horses will be present this year at the expo, down from 300 in recent years, expo President Glen Eaton said. But organizers say there will still be plenty of entertainment, and they hope to draw the usual 45,000 human visitors.

Cases of equine herpes virus-1 (EHV-1) crop up every fall and spring, said Dr. Paul Anderson, assistant director of the Minnesota Board of Animal Health. But this year has seen an unusually high number of cases reporting neurological symptoms, which can be deadly.

"We're concerned about what's happening here," Anderson said.

In Minnesota, where the ailment has been most prevalent, seven horses have tested positive for the virus, two of which had to be euthanized, Anderson said. The other five are recovering.

Olissio Zoppe made his way back to a horse barn after he practiced with his horse.

The last reported case in Minnesota was on March 29 in Wright County, according to the Animal Health Board.

In Wisconsin, the most recent of two confirmed cases of the virus was reported on April 8. One case has been reported in Iowa.

While Minnesota has not declared an official quarantine, a rare, voluntary two-week ban on equine travel was strongly recommended for Minnesota horses by Anoka Equine Veterinary Services, which serves horse owners in the Twin Cities metro area. That voluntary ban ended Tuesday, according to Anoka Equine veterinarian Dr. Tracy Turner.

The 50 or so horses at the expo will be limited to Professional Rodeo Cowboys Association rodeo stock and participants, Ma'Ceo show horses, clinician presentation horses, and wagon ride horses, according to Kathy Juhl, the expo's marketing director. Those will include a number of Minnesota animals, as well as some from out of state. Breed and registry groups and private farms and stables cannot bring horses to the expo.

"I believe we've taken very good precautions," said Turner, who is also president of the Minnesota Horse Council, which puts on the expo. "We've taken more precautions than we've needed to. We take this very seriously."

Even with what Turner called "a lot of panic" in the horse community, he expects a typical visitor turnout of about 45,000 at the expo, which will feature 400 vendors in addition to horse shows.

Beyond limiting the number of horses, the expo will take several other measures, Turner said. Before horses can even enter the expo, owners will need to present a health certificate issued within a week before the event. The 50 horses will be spread across three barns to decrease the amount of contact. Horses will have their temperatures taken twice a day.

Visitors will not be allowed to touch the horses, and hand sanitizers will be ubiquitous, Eaton said. All visitors will receive a fact sheet about the virus and how to prevent it, and educational sessions will be offered daily, Juhl said.

Eaton said that in his 20 years with the Minnesota Horse Expo, he has never encountered a similar situation.

The reaction from the horse community on the expo's precautions has been mixed, Anderson said, but he stressed that the event will "still be fun."

On Wednesday, Richard Winters, a presenter from Nevada, was among those preparing for the expo at the fairgrounds. He said he had no hesitation about bringing two of his clinician horses to Minnesota. The precautions taken by expo organizers give him confidence that his horses will stay healthy, he said.

The show will go on

EHV-1 is a non-neuropathogenic virus strain that sometimes has neurological symptoms, Anderson said. The virus is not uncommon, and its symptoms generally include fever, respiratory illness or spontaneous abortion, according to the Board of Animal Health. But multiple cases of EHV-1 with added neurological signs are unusual.

Afflicted horses may have difficulty with their back legs, show poor coordination because of the virus' effect on the spinal cord and have trouble urinating.

The animals spread the virus among themselves via nasal secretions and horse-to-horse contact. While humans are immune to the virus, they can spread it via their hands and clothes to the horses, as well as through grooming tools and water and feed buckets, according to the University of Minnesota Center for Animal Health and Food Safety. The virus can also be spread by sharing grooming tools, tack and water and feed buckets.

This virus doesn't live outside the horse very long, Anderson said. Hot air and sunshine kill it quickly. "Hopefully the sun will shine and the weather will get better and this will quiet down," Anderson said.

Juhl said she understands that people may be upset that fewer horses will be present, but wants them to know the schedule will still be full each day with high-quality entertainment.

"[We] just don't want to discourage people from coming," Juhl said. "It's regrettable, but we're still going to go on."

Danielle Dullinger is a University of Minnesota student reporter on assignment for the Star Tribune.