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VEE, a mosquito-borne infection from South America, invaded Texas last month, threatening to devastate the U.S. horse industry. It was stowed by a serum first developed in 1943 from a dead jackass

The 1971 Kentucky Derby was less than two weeks away when a U.S. Department of Agriculture employee rushed into the Hyattsville, Md. office of Dr. Richard Omohundro, assistant director of the USDA's Animal Health Division. "There's some South American horse waiting for clearance at the Miami airport," he said. "He's on his way to the Derby, but he hasn't got a health certificate."

"Well, he can't race without one," Omohundro said. "Have him put in quarantine and kept there." Fortunately for Canonero and the national pride of Venezuela, the certificate arrived shortly afterward and the horse was released in time to make his bid for immortality.

Early this summer another Venezuelan arrived in the U.S. by air, but this time there was no question of holding it at the airport. The second visitor came across the U.S.-Mexican border somewhere near Brownsville, Texas around the first of July, traveling by mosquito. Before this traveler was slowed down last week, more than 1,400 horses lay dead along the Texas Gulf Coast, and the $12-billion U.S. horse industry was threatened with disaster.

By curious coincidence, the same man who nearly stopped Canonero—Richard Omohundro—also led the holding action against VEE, Venezuelan equine encephalomyelitis. In the second instance it took more than a phone call and the muscle of the Federal Government; before Omohundro would relax last week in his Houston motel room and discuss the campaign at leisure, more than 4,000 persons in 11 states had been marshaled to battle the disease; over one million inoculations had been given; six states had been slapped with a federal horse quarantine and race commissions and tracks from New York to Tijuana were slamming their stable doors to incoming horses from the endangered areas. In Ireland, England, France, Italy and West Germany, governments issued a total embargo on U.S. horses for an indefinite period.

VEE, sometimes called the blind staggers for the debilitating effect it has on horses, kills four out of every five animals it infects. It is an entirely new strain to this country, although, since 1936, it has drifted north from Venezuela through Central America. Other strains of equine sleeping sicknesses have appeared sporadically in the U.S., the most recent serious case being the 1959 epizootic that resulted in the death of 21 persons and 52 horses in New Jersey.

On July 9 the first two VEE horse fatalities in U.S. history were confirmed at Brownsville. Within two weeks perhaps 1,100 horses had died in the same area, and the disease appeared out of control and heading north, east and west simultaneously. It would have been better drama if Dr. Omohundro had entered at this point, grappled with the dread microbe and, after a bunch of sleepless nights and grueling days, saved the equine from extinction on this continent. Actually it wasn't quite like that. Omohundro, at 56 a balding, down-home version of Robert Mitchum, had had his eye on VEE for some time. And what he saw as early as mid-May was an estimated 6,000 Mexican horses dead of VEE (another estimate said the number was closer to 12,000), some as near as 250 miles from the Texas border.

Reports of hysteria were reaching Washington, and not all of them were coming from south of the border. Texas ranchers were watching VEE even closer than Washington, and their message was clear: Do something, fast. But Washington couldn't declare a national emergency until the disease crossed the border. Although earlier cooperative efforts by U.S. officials to stem the spread of the disease in Mexico were now intensified, certain international amenities still had to be observed. "We couldn't just march down and say this is what we're going to do," Omohundro said. "That just wouldn't be right."

By June, 12 cases of VEE were confirmed only 100 or so miles from Texas, and the USDA sent down veterinarians to help. Vaccinations were begun, but the Mexican government required one of its vets to accompany each American, and a job that cried for speed was creeping along. Many Mexicans with still healthy horses were afraid of the vaccine, called TC-83, which uses live VEE virus. The first serum was developed from the brains of a dead jackass in Trinidad 28 years ago. The vaccine was listed as experimental, and many farmers feared it would cause VEE, rather than prevent it. About this time it began to rain hard, and now the carrier mosquitoes had thousands of new breeding spots, and the threat to U.S. areas grew measurably. On June 18 the USDA banned all Mexican horses from entering this country, and a few days later U.S. forces retreated north of the border to Harlingen, Texas, 20 miles from the marshy, mosquito-rich Gulf shore.

At this point Omohundro was still in Hyattsville, coordinating Government personnel from all over the country in and out of Harlingen. Veterinarians and technicians came from Washington; the U.S. Public Health Service sent virologists and entomologists; Air Force spray planes flew in; and within Texas the Department of Health and the Animal Health Commission supplied help. The entomologists began studying mosquito populations, but there was debate on when and where to spray. Vaccine was distributed to veterinarians in 13 South Texas counties, but its use was voluntary, and too few horse owners took advantage of it. Others, like the giant King Ranch 100 miles north of Brownsville, began immediate vaccination. "We were the first," said the ranch veterinarian. More than 2,000 animals were inoculated there, and no illness was reported.

Then, sometime late in the last week of June, VEE entered the United States. On July 11, two days after Texas' first two horse deaths from VEE were confirmed, there were 44 suspicious cases in four Texas counties: Cameron, Hidalgo and Starr, at the border, and Aransas, 135 miles and six counties north of it.

The symptoms were all similar, and all ghastly. Within two to three days of infection the animal's temperature soars to 103°-106°. The horse becomes listless and depressed. Soon the blind staggers set in, and the horse stumbles about in circles or stands helplessly, often cross-legged. Within six to eight days, death occurs in 80% of the cases. Fortunately, human symptoms are milder, resembling influenza, and other nonequities seem immune. No human fatalities from VEE have been reported in the U.S.

Some officials blamed the erratic spread of the disease on hysteria. In Brownsville, panicky horse owners were seen loading their animals in trucks and heading north. "They thought they were escaping," said one vet, "but the horses were already infected, and they were just spreading it."

Dr. Gary Crouch, the Brownsville veterinarian who diagnosed the first U.S. cases, spoke of driving down a nearby road in the second week of July and seeing nine dead horses on the shoulder in one three-quarter-mile stretch. "They were dying all over the place," he said. "One man lost 12. The woman next door lost five out of six."

"We're unable to assess the number of dead," said Dr. Perrian Henry, federal coordinator at Harlingen, at the height of the epizootic. "I guess we've lost this battle, but we haven't lost the war." And the fight raged on.

On July 14 the USDA placed a federal quarantine on Texas. No horses or other equines would be allowed out of the state unless vaccinated at least 14 days prior to shipment. To this point VEE had been moving considerably faster than the wheels of the various bureaucracies seeking to contain it, and many Texans were critical of USDA efforts. By mid-July, when VEE was known to have been in this country for less than two weeks, Omohundro requested that Secretary of Agriculture Clifford M. Hardin declare a national emergency. Next day, Hardin agreed. The move was made, said Hardin's statement, " control and eradicate the disease wherever found," and in effect the campaign got a blank check to meet the emergency. The first step was to establish an east-west cordon sanitaire of vaccinated horses across Texas. Meantime, intensive spraying was begun and the states of Louisiana, Arkansas, Oklahoma and New Mexico shortly were added to the federal quarantine. A sixth state, Mississippi, was included later.

On July 18 Omohundro canceled a two-week family camping trip to Nova Scotia and flew to Texas to coordinate an anti-VEE task force of 80 men and women from 23 states that began moving into the sprawling Field Inn North motel outside Houston. Omohundro's defensive strategy depended on three weapons: the quarantines already imposed, mosquito spraying and vaccinations. He appointed men to administer each, and the USDA team went on 24-hour call, seven days a week.

To evaluate the effectiveness of their campaign, Omohundro's men tried to determine how many horses VEE was killing in Texas each day. But that proved impossible. To detect the presence of VEE, blood and tissue samples have to be taken while the horse is still alive or within half an hour after death. Otherwise the tests are inconclusive. Unfortunately, horse owners were seldom anxious to keep a dead horse around, or to call in a vet immediately after one had died. Many animals were simply buried, quickly, and so Omohundro's diagnosticians had to depend on luck or some rancher's inspiration. One call lured scientists on a two-hour drive at the end of which they found a horse that had been killed by a truck. Others were easier to find, but not all owners were cooperative. One Port Isabel rancher lost 30 head and was obviously miffed by the official inquiries. "All they can do is drive up and down the road asking how many dead horses have you got," he said. "I told one of 'em he should ask how many live horses I've got. I told him if another man asks me how many dead horses I have I'm going to whip him."

Texas politicians and newspapers were displaying some of the same impatience. U.S. Representative Eligio de la Garza said he had tried to get the USDA to fight the disease in June, before it reached Texas. And the Houston papers asked why the vaccinating wasn't started before the epizootic began. Dr. Omohundro responded to such questions succinctly. "I didn't make the decision when to start this program," he says. "I was just sent here to do a job."

One day after the Houston operation began, mosquito control planes were starting the largest aerial spraying operation in history. It covered the entire Texas coastline, part of Louisiana and a 130-mile stretch up the Rio Grande River, about eight million acres of potential mosquito breeding spots altogether. On the ground, meanwhile, a team of 26 entomologists was making mosquito counts—one of the methods was to walk into a swamp area (without benefit of insect repellent or special protective clothing) and see how many mosquitoes landed on you in two minutes. Only nine of the 26 men had been vaccinated against VEE. "We're not trying to kill all the mosquitoes," explained the chief entomologist at Houston, Dr. Robert Hoffman. "We're just buying time until they get 90% of the horses in Texas vaccinated."

It seemed a straightforward task, if not a simple one. Early estimates had put the number of horses there at 450,000, but it was soon apparent that someone had miscalculated. By the first week of this month Omohundro's men had already vaccinated 548,000 head, meaning the state had a phantom horse population of 100,000 or more. The trouble was statistical, of course. The last horse census taken in Texas was in 1960, and since then, as in most states, the horse population has more than doubled. At one point, therefore, Houston was estimating the figure to be more than a million, but later it was dropped to 700,000. And by this week the 90% vaccination level had been passed.

Another mystery is just how many horses have actually died of VEE. Statisticians were estimating that 1,957 horses became ill from all causes during the critical period, and that 1,411 had died—again from all causes, including other illnesses, as well as accidents and old age. Nobody will ever know how many of them died from VEE, but certainly the toll was heavy. All anyone will say for sure is that the death rate has dropped sharply since Aug. 1. "I hope one thing that comes out of this emergency is a good disease-reporting system," Omohundro commented.

Nobody outside of Texas, apparently, is taking any chances that VEE might leap suddenly to a new state, or even across the Atlantic. Quarantines by racetracks across the country are still in effect for unvaccinated horses from the critical areas, and the European embargoes are as stringent as ever. In New York, Roosevelt Raceway's prestigious International Trot this month may have to be canceled because European owners, especially the French, are reluctant to send over horses and have them stranded here because of the embargoes in their own countries. "The ban will remain until it is absolutely clear there is no further danger," said one British authority. France may continue its quarantine indefinitely. In previous epizootics, some nations have kept their bans in effect for as long as two years after the last reported case.

Things are relatively calm at the Field Inn North this week. Most of the office lights have been going off around six, and Dr. Omohundro even managed a round of golf one morning. The phones still ring constantly during the days, and the Houston radio and TV stations continue to call, but they aren't getting any more lead stories. Dr. Omohundro is busy writing letters of commendation to members of the motel staff, his secretaries, just about everyone who's helped out in any way over the past month. He speaks matter-of-factly about what has been accomplished in Houston, but when someone asked him what would have happened if VEE had just been allowed to run its course, he stood up and slapped his palm to his forehead.

"Without a program there would have been utter chaos in this country's horse industry," he said. "I've been in this business 34 years, and I've never seen anything that stirred people up so emotionally as this." One of his field-men told Omohundro of an incident during this plague that summarized the tragic toll VEE has exacted from the horse owners of Texas. He had just returned from Corpus Christi, where he had talked with a girl whose horse had died. He asked her how much the horse was worth. "Do you mean how much did we pay for him," she asked, "or how much was he worth?"



Equipment from the Texas Highway Department removes the carcass of a horse that died near the Mexican border at height of the plague.


Dr. Omohundro (standing at right) confers with his staff in their Houston motel headquarters.


Victor Norman bows his head in sorrow as veterinarian prepares to put his horse to sleep.