BOISE, Idaho -- When cowgirl Tricia Lynn Crump rides in the annual Parade America in Idaho on Saturday, the state's reigning Miss Rodeo won't be astride a horse.
Like many riders throughout the west, Crump is worried about an outbreak of a deadly and highly contagious virus that's infected at least 34 horses in nine states and Canada at the height of show season. Horse shows and sales have been canceled and some competitors are backing out of the professional rodeo circuit.
"I go out of state a lot, and I would really like to protect my horses when I'm not able to check on them all the time," said Crump, who will instead ride a stagecoach in the parade in Nampa, about 20 miles west of Boise. "I think we tend to forget and let our guard down when we trailer out to different arenas."
At least seven horses have died from the virus, Equine Herpes Virus-1, which poses no risk to humans and can be airborne and transmitted by touch or by sharing feed, brushes, bits and other equipment.
More than 1,000 animals are known to have been exposed through direct or indirect contact with infected horses, which are among 400 that attended the National Cutting Horse Association Western National Championships in Ogden, Utah earlier this month.
Cutting competitions – in which horses and riders are judged on their cattle-handling skills – involve quarter horses or other stock-horse breeds. But all horses are susceptible to the virus.
Fewer people are showing up to compete on a professional rodeo circuit. Organizers of one group sent out an alert to members reminding them not to share equipment or water troughs and to take other precautions.
"It's not just the contestants – the rodeo committees have a lot at stake," said Cindy Schonholtz with the Professional Rodeo Cowboys Association. "The stock contractors that own the bucking animals, the pickup men who work in the rodeo pen – we're monitoring the situation basically by the hour to keep everyone updated."
Colorado State Fair organizers have canceled three horse events in Pueblo. An event billed as the nation's largest horse sale in Billings, Mont., was postponed. The Big Loop Rodeo in Jordan Valley, Ore., has told contestants their entry money will be refunded and the event will be rescheduled for this fall.
In Washington, the Kitsap County Sheriff's Posse is pulling out of Saturday's Armed Forces Day Parade in Bremerton, and the Washington Cutting Horse Association canceled its first show of the season, which was scheduled for this weekend.
"Basically, we're trying to get everybody to stay home for two or three weeks until we get this thing cleaned up," said Jeff Sleeman, a member of the group's board of directors. "Our organization decided that in the best interest of the equine that we should have not have the event this month."
The number of infected horses is likely higher than the official count, which comes from the federal Animal and Plant Health Inspection Service. The agency relies on states to report their own numbers.
Infected animals usually get sick between two and 14 days after they are exposed to the virus. Symptoms include fever, sneezing, staggering and partial paralysis.
Colorado has the most confirmed cases so far, with 9 horses testing positive for the virus and two that died. Other states had greater potential exposure – like Oregon, where 140 animals have been exposed to the virus – but fewer actual cases.
Utah state veterinarian Bruce King said it may be impossible to track down all the sick or exposed animals. The first reported cases came from Weld County, Colo., so King said he didn't find out about the outbreak and the link to Ogden until he got a call from Colorado's state veterinarian last week.
King immediately began trying to track down every horse and owner that was at the Ogden cutting show, putting two of his field veterinarians on the job full-time. But he ran into some roadblocks.
Not every horse at the show was listed or registered with the show organizers. Those that were didn't always have up-to-date addresses.
National Cutting Horse Association officials did not return calls from The Associated Press.
By the time many of the owners were notified, they had already attended other events. Some people didn't find out about the outbreak until their own animals got sick – including a woman who left the Ogden cutting competition, then competed with the same horses in Arizona and was going to a cutting competition in California when her animals started showing symptoms.
Maureen Long, a large animal veterinarian, assistant professor at the University of Florida and infectious disease specialist, says having animals that are unaccounted for could present a "huge problem."
"We want people to do pre-event planning, where they account for every animal that walks on the place," Long said. "If they didn't do that, they'll never know where-all this virus went. It's just like flu on a doorknob. It's not going to live there forever, but it's going to live long enough to infect horses."
Florida learned the hard way how to deal with outbreaks, she said. An outbreak at a racetrack in Wellington, Fla., in 2006 infected just 13 horses and killed about half, but it took 10 days before veterinarians identified the virus. A handful of other sites were infected in the meantime, she said.
"It took the state 4,000 man hours to do the trace back, and that doesn't include veterinary hours. It cost the state a whole lot," Long said. "Sites were quarantined for between four and eight weeks. There were closures or limited work for three veterinary practices, and the show season was delayed for three or four weeks."
Associated Press Writer Sue Manning in Los Angeles contributed to this report