By ANDREW BRIDGES
AP Science Writer
LOS ANGELES
– All California horse owners should vaccinate their animals
against the West Nile virus before the disease hits the state with
full force this summer, local veterinarians say.
By ANDREW BRIDGES
AP Science Writer
LOS ANGELES – All California horse owners should vaccinate their animals against the West Nile virus before the disease hits the state with full force this summer, local veterinarians say.
“This is a mosquito-borne disease, so any horse is susceptible,” office secretary Debi Kent tells people who come into the Tri-County Veterinary Hospital in Gilroy. “We’ve been doing lots of new ones recently and we’ve been offering it to clients when they bring their horse in for routine checkups.”
While only 1 percent of humans infected with West Nile virus become seriously ill or die, the disease is fatal to as many as a third of all horses that contract it, said Gregory Ferraro, director of the University of California, Davis, Center for Equine Health. Those that survive can suffer from long-term or permanent disabilities.
“California’s horsemen should heed the lessons learned by other states,” Ferraro said. “West Nile virus is a potent pathogen that has the capacity to infect large numbers of horses in a short period of time.”
Vaccinated horses require yearly boosters after receiving the first two rounds of the shot, typically spaced three to four weeks apart.
Since the mosquito-transmitted virus was first reported in New York in 1999, it has quickly spread westward. It first appeared in California last summer, where a single case involving a horse was reported. A single human case also was reported. Health officials remain uncertain how that person was infected.
The horse likely was infected in Nebraska and transported to California, Ferraro said. Nationwide, nearly 15,000 horses were infected by West Nile last year.
Ferraro said Tuesday that the state’s estimated 1 million horses should be vaccinated before the summer’s peak mosquito season.
“The virus will undoubtedly be here, undoubtedly there will be horses that get infected and undoubtedly there will be horses that get sick and die,” Ferraro said.
A horse vaccine became available in 2001, under conditional approval by the U.S. Department of Agriculture. The vaccine, made by Fort Dodge Animal Health, was granted full approval last month.
It has been found effective in warding off the illness in horses with 95 percent efficacy, according to the company.
There is no human vaccine.
Many owners have already vaccinated their horses. At Whispering Willow, a Glendale stable, the “vast majority” of the 50 horses have received the vaccine, stable manager Maria Crone said.
“The attitude is, it’s going to be here and better safe than sorry, and it’s not outrageously expensive and is generally a good idea,” Crone said.
The two-shot series costs roughly $70 to $100.
Nadette Raymond, president of the California State Horsemen’s Association, said she had her seven quarter horses and other horses vaccinated last fall. Many of her 30,000 members have followed suit.
“As soon as the vaccine was available, we vaccinated them,” said Raymond, who lives outside Redding. “We cannot afford to lose these $15,000 horses.”
Other vaccinations typically given December through May include: eastern and western encephalitis, tetanus, influenza, rhinopneumonitis and rabies.
Staff Writer Eric Leins contributed to this report.
For more information, contact Tri-County Veterinary Hospital at 848-8886.
On the Net: UC Davis Center for Equine Health: www.vetmed.ucdavis.edu/ceh/
