West Nile vaccine approved

By LYNN MONTGOMERY | East Texas Edition

While many horseowners are focused on births of new babies, it's also time to be considering vaccinations against West Nile Virus. Just recently, Fort Dodge gained full license for the vaccine. Horse owners are urged to talk to their veterinarian about a complete vaccination program. -- Staff photo by Montgomery

March 13, 2003 -- For horse owners, springtime means foaling and annual vaccinations. One vaccination horse owners may be considering is one to protect their animals from West Nile Virus (WNV). Last year, this vaccine was under a conditional status while efficacy studies were performed.

According to a press release issued Feb. 6, Fort Dodge Animal Health was issued a full license by the U.S. Department of Agriculture (USDA) for the West Nile Virus (WNV) vaccine called West Nile-Innovator™.

Denise Charpentier, with Fort Dodge, stated the efficacy studies submitted to the USDA by Fort Dodge demonstrated the vaccine is "immunogenic and efficacious." According to the study summary, 95 percent of the horses vaccinated with two doses of the vaccine, and challenged with the live virus 12 months later, were free from viremia (virus in the bloodstream) versus 82 percent of the non-vaccinated horses developed active WNV infection, as evidenced by recovery of the virus from blood samples.

"Horse owners and veterinarians can be confident this is a safe and effective vaccine to aid in the prevention of this potentially deadly disease," explained Lynn Bixler, equine product manager for Fort Dodge.

WNV, according to Fort Dodge, is one of the fastest growing health threats to horses today. The virus, spread by mosquitoes, originates from blue jays, crows or hawks.

As of Dec. 31, 2002, the total number of equine cases involving WNV infection confirmed by the USDA's National Veterinary Services Laboratory or reported by state officials was 14,717, an increase of over 13,000 cases in just one year, according to a Fort Dodge news release.

"You don't know where it (WNV) is going to pop up," said Dr. Randal Bennett, Quitman Animal Clinic. "It is sporadic depending upon the bird population.

Bixler added, "Up to 40 percent of horses who have been diagnosed with WNV have died or been euthanized. Vaccination prior to exposure is the single most important tool in protecting the health of these animals. Prevention is the best approach toward this deadly disease."

West Nile-Innovator™ is available from licensed veterinarians only and cost ranges from $16 to $20. Previously vaccinated horses will need a booster shot. If the horse has not been vaccinated at all, the initial vaccination consists of two injections given three to six weeks apart.

Veterinarians also urge horse owners to vaccinate against other common encephalitises - Eastern Equine Encephalitis and Western Equine Encephalitis. Talk to your veterinarian about a complete vaccination program.