ORIGINALLY WRITTEN CYNTHIA MARTENS
Horses contracting the West Nile Virus have been reported in Kansas, and the number of animals testing positive is growing.
“We anticipated (the West Nile Virus) hitting this summer,” said veterinarian Norman Galle of Hillsboro Animal Clinic. “But it’s moving very fast and covering the state.
“It’s already in Colorado, and they expect it to be in California now by the end of the year-it’s a little unusual how fast it’s spread.”
But so far, no horses in Marion County have tested positive, according to area veterinarians contacted.
The virus is an encephalitic disease like eastern and western encephalitis, Galle said.
Migratory crows and blue jays are the No. 1 carriers, he said.
The disease is spread by the bite of a mosquito that fed on an infected bird. It can’t be spread from horse to horse, horse to person or bird to person.
Medical authorities indicate human cases are rare, and none have been discovered in Kansas. All evidence indicates the virus is limited to equine animals, such as horses, ponies, mules and donkeys, and does not affect cattle.
The virus was isolated in Africa in 1937 and first appeared in New York City in late summer, 1999.
“A lot of horses will be exposed to it, but very few get sick from it,” Galle said. “There’s a small percentage-probably less than 1 percent of the population-that actually gets sick by an infected mosquito.”
Of the horses that are infected and show signs of the disease, 40 percent die from it, he said.
The virus causes the brain and spinal cord to swell as part of the disease process. Symptoms include loss of balance, paralysis, muscle twitches and lack of coordination.
“The horse will be laying down, not wanting to get up or move around,” said veterinarian Jessica Laurin with the Animal Health Center of Marion County.
Galle and Laurin both recommend vaccinations for their clients’ horses.
Laurin declined to quote the price of the vaccine because various factors determine the cost, and said it’s best to check with the individual’s veterinarian of choice.
“We went through 200 doses this summer,” Laurin said. “And I ended up with another 80 doses, which are already spoken for.”
Galle said he has vaccinated about 100 head so far.
“Most of it’s been in the last two weeks since they confirmed a case in Kansas,” he said. “Most people have gotten concerned.”
The manufacturer of the vaccine recommends the first shot be given by the veterinarian, Laurin said. The vaccine is injected into the muscle of the horse’s neck.
“We request that horse owners get in contact with us,” she said. “And we can vaccinate the horses here at the clinic, or I have been going to farms, as well, to give the vaccines.”
A second vaccination, a booster, is recommended about three to six weeks after the initial shot and can be given by the horse’s owner.
“We called the manufacturer, and they recommend an annual booster,” Laurin said. “So after the booster, they should get a booster once every year for the next two to three years.”
If a horse contracts the disease and lives through it, there’s a good chance it may not be as usable as it was previously, she said.
“Maybe you can’t ride the horse, maybe it won’t have very good eyesight, or maybe (the horse will) lose its balance.”
Galle said if a horse contracts the disease, there is no treatment and veterinarians are limited to supportive measures for the ailing horse. He also cautioned the public to be aware of keeping the mosquito population down. (See sidebar below.)
Although few horses may actually be exposed to the virus in Kansas, Laurin and Galle agreed the situation warrants action.
“At this point, we’re seeing enough of the virus in Kansas that we’re encouraging people to vaccinate,” Galle said.
