Since the West Nile virus vaccination has been made available this year, more horse owners are taking precautions.

Dr. Willem DeHoogh, a veterinarian at Stateline Veterinary Service in Adams, has given many vaccinations this spring and summer.

"I don't even know how many," DeHoogh said. "A lot of clients are interested and not taking any chances."

Earlier this week, two dead crows in Minnesota tested positive for the West Nile virus. Three horses have been exposed and one has died.

The virus is carried in birds, especially crows, and transported to humans and animals by mosquitoes.

The West Nile virus has not been discovered in Mower County as of Saturday.

The West Nile virus is rare in humans. Less than one person out of every 150 who are exposed to the virus develop it, according to the Minnesota Department of Health.

And of those who contract the disease, about 13 percent of them develop encephalitis, said Arlis Clennon, Mower County public health nurse.

Those who are at most risk are children and the elderly because their immune systems are weaker, she said.

"The majority of people who are infected usually have mild illness," Clennon said. "They usually don't know they have it."

The main symptoms are similar to other encephalitis infections, which include fever, headache, stiff neck and vomiting, she said. These can progress to confusion and mental changes.

There is no medication to combat the virus.

Avoiding mosquitoes is a way to protect against the virus. Clennon suggests staying indoors during the early morning and evening, when mosquitoes are more likely to be out. Wearing bug repellent with DEET and long pants and sleeves also repels mosquitoes.

Birds are at the most risk for the disease. Horses and humans are next, said DeHoogh. Other animals may become infected, but it's rare, he added.

Horses display similar symptoms as humans, such as fever, disorientation and appetite loss. One-third of the horses that were diagnosed with the disease die from it, DeHoogh said.

"It's not going to kill every horse that gets exposed," he said.

Horses who get the virus should be given a lot of fluids and maybe some aspirin, but it's up to the immune system to fight it, DeHoogh said. Healthy horses may not even show symptoms.

Vaccinations given by veterinarian cost total about $30. The horse needs two shots and the vaccine doesn't take effect until the second shot, which is administered three to six weeks after the first, DeHoogh said.

Those showing their horses at the Mower County Fair should not worry about contracting it at the fair. The grounds are sprayed for mosquitoes.

The grounds do not have stalls to keep horses in overnight so the horses won't be around each other the whole week, said Denice Mudra an organizer of the fair.

"Nothing has been corresponded to us from the state," Mudra said.

Dr John Stevenson, a veterinarian at Austin Veterinarian Clinic, who consults with the fair board, said that the chance of a mosquito biting an infected animal and then infecting another animal is very slim.

"There's not major concern," Stevenson said.

Cari Quam can be reached at 4343-2235 or by e-mail at :mailto:cari.quam@austindailyherald.com