Honoring 50 Years of Vigilance Against Equine Disease

It must have become rather irritating for virologists, over the past couple of years, to hear so many of us appointing ourselves overnight experts on the best ways to tackle a pandemic. But that was a familiar enough experience for Dr. Peter Timoney, thinking back 20 years to the harrowing time when the Bluegrass was gripped by panic over Mare Reproductive Loss Syndrome (MRLS).

At the very time when his skills were most precious, as a world authority on equine virology based right there at the University of Kentucky, so his toil became most literally thankless.

“Oh yes, you feel like you're in the stocks,” he recalls. “And of course the expectation is that you should have had 20-20 hindsight. 'Why didn't you do this, why didn't you do that?' It all became very fast and furious, human nature being what it is…”

He permits himself one of the wry chuckles seldom far away in conversation with this immaculate figure, dapper and courteous, whose true standing in our community can be more accurately judged by the Lifetime Contribution Award he has just received from the Kentucky Thoroughbred Association/Kentucky Thoroughbred Owners and Breeders. As their citation declared: “There is no one more respected or admired on the topic of infectious diseases, either locally or internationally, than Dr. Peter J. Timoney, MVB, MS, PhD, FRCVS, professor and Frederick Van Lennep Chair at the Gluck Equine Research Center.”

But the alphabet soup and formal distinctions, which could be infinitely extended, feel almost incidental to the still greater status implied by the first half of that sentence—nourished, as it is, by a tireless spirit of inquiry and service. In the words of one of Kentucky's leading farm managers, Timoney is “on speed-dial for any equine laboratory in the world where they stumble across something that makes them uneasy.”
While grateful that his community had sought to ease the wrench of retirement, Timoney reflects on his award with resolute modesty.

“It was very thoughtful of them and I was deeply honored in that I didn't deserve it, frankly,” he says. “Not that I haven't been involved in the industry, on both sides of the Atlantic, for a very significant number of years. In fact, it's 50 years since I became species-specialized. But for me there was no greater pleasure or distinction to the day than the presence of Mr. Bassett.”

A significant span even of Ted Bassett's years measures their friendship. They recently shared a meal in the Keeneland track kitchen. John Williams was sitting on the adjacent table and the next thing Timoney knew the pair had broken into song. “Oh, it was choice!” he exclaims—an expression that quaintly captures the Irish lilt, light and precise, he retains after all these years.

And suddenly, no less typically, you realize that we're no longer talking about the latest of Timoney's many awards.

It turns out that he prefers to discuss his own limitations, and those of his field. These latter, of course, diminish all the time–which goes a long way to explaining Timoney's reluctance to take things easier now. But like a general who learns to read the mind of his opponent, through a long siege, he will never lose his awe for the way Nature, in her most aggressive garb, is always one step ahead.

“How many viruses have we truly eradicated?” he asks. “Two, smallpox and rinderpest. That's it. It would be counter-productive for a virus to eliminate the host species it infects. You take African Horse Sickness. In Equus caballus, the domesticated horse, certain forms of the disease can kill 90 to 95 percent of infected individuals within a week of exposure. What about mules? Yes, they become sick but the mortality rate is less, maybe 50%. As for donkeys, it depends on the type under discussion: in European donkeys, the virus can kill 40 to 50%. But this doesn't occur in the case of African donkeys that survive the infection. They've been around for a considerable period of time. Given time, agents and their hosts learn to adapt.

“Nature is amazing. Take bats, the single largest class of Mammalia: an estimated 6,000 different species. Sources of rabies, SARS-1, SARS-CoV-2 viruses: none of which clinically affect them. But by golly, look what they're capable of causing in humans.”

Timoney will always cherish insights obtained as a graduate student in the 1960s, when privileged to sit in on meetings between then prominent pioneers in arbovirology (i.e. studying arthopod vectors like mosquitoes). “Endowed by instinct and very strong observational skills, they had worked out how certain viruses spread to humans and persisted in nature,” he says. “A forerunner to what was subsequently expanded upon in the era of molecular diagnostics. I'll never forgetting listening to Karl Johnson describing what he had discovered in relation to Bolivian hemorrhagic fever, caused by Machupo virus which can give rise to fatal infections in humans. At the time there was no idea how people became exposed to the virus. He investigated a range of species of rodents and found that one, a small mouse, Calomys callosus, was susceptible to the virus and became persistently infected with it–but that the virus didn't kill it. The virus localised in the kidneys and was shed in the urine. Individuals unfortunate to come in contact with contaminated food or any fomite [material carrying infection] ran the risk of being exposed to the virus and many developed the disease.”

One of Timoney's early mentors was “one of the true virus hunters”, a Texan who had spent many years working in Africa and South America and identified a number of arboviruses; and had previously worked under Dr. Kenneth Smithburn, who discovered West Nile virus in Uganda in 1937. Timoney embraces that sense of the baton being passed, from one generation to the next; the perseverance and accretion of science. In that vein, he urges graduate students today to go back and see how remarkable was some of the deductive work published in 19th Century medical journals, when laboratory diagnostics was still in its infancy.

“Some of those papers are tremendous introductions,” he says. “I think our powers of observation and reasoning are not perhaps as finely tuned as they were in early investigators. We're spoilt today by the wealth of advanced diagnostics available to us.”

Now that technology has made deep sequencing far more affordable and rapid than even five years ago, it is possible to identify additional agents that have never been recognised or that used to be described as “orphans” because they couldn't be linked to a specific disease.
Such efficiencies are critical whenever science finds itself in a race against the clock to trace the cause of new disease. It's hard to imagine the sinking feeling that Timoney must have experienced when MRLS hit. While hindsight, as he has already remarked, is all very well, he reflects wistfully on the time, a couple of decades previously, when one of the biggest breeding farms in Kentucky sent expelled foetuses for analysis that could well have represented cases of MRLS.

“A species of streptococcus was being isolated that we felt at the time wasn't the cause of the problem,” he recalls. “But what we didn't know was there was a background surge that year in the population of tent caterpillars. In 2001, the latter were everywhere, they were to be found in the suburbs of Lexington. One couldn't walk outside without scrunching them underfoot. The horses were ingesting them in the course of grazing, and the setae on the integument of the caterpillars were piercing the wall of the small intestine. Bacteria from the alimentary tract were carried via the bloodstream to the pregnant uterus. It was terrible, upwards of a third of all pregnancies being lost that breeding season. A terrible consequence for the industry to bear.”

By the following year, farms were adapting. They cut down cherry trees, and either kept mares indoors or muzzled them at pasture. Timoney's vocation certainly calls for a thick skin. He remembers, as a young vet in rural England seconded to the British Ministry of Agriculture to assist in an outbreak of foot and mouth disease in the late 1960s, how the associated depression in some instances led farmers to take their own lives.

“The first cases I saw of this dreaded disease involved the No. 3 Ayrshire herd in England,'” Timoney recalls. “And all I could do was share in the misery and grief of the farmers affected. The images of the resulting desolation never leave you.”

Timoney had actually been drawn into the horse world in the slipstream of another crisis. He was still working with cattle and sheep diseases when a number of prominent Thoroughbred studs in the south of Ireland were struck by the neurologic form of Equine Herpesvirus 1 in 1972. That prompted the Department of Agriculture to re-assign him to head up a new equine diseases section at the Central Veterinary Research Laboratory.

After an extensive training period in the U.S. and Canada, he established and headed up the new section for six years until in 1979 accepting an associate professorship in virology at Cornell, where he supervised a high volume multi-species diagnostic service. After a couple of years or so, he returned to Ireland to assist in planning and developing an Irish Equine Centre before in 1983 taking a full-time research position in the University of Kentucky Department of Veterinary Science. He served as department chair from 1989 to 2008, and director of the Maxwell H. Gluck Equine Research Center from 1989 to 2006.

Those years encompassed immense changes in racing and breeding, above all in the frequency and range of international horse travel. The challenge today is to facilitate that movement while mitigating the risk of disease transfer to an acceptable level. Timoney is confident that it's possible to achieve this goal using the High Health, High Performance framework and, when indicated, the Equine Disease-Free Zone concept.

“While I'm a very strong proponent of the facilitation of international horse movement, my greatest worry is the risk of introducing a disease into the U.S. that might have catastrophic repercussions,” he says. “At the end of the day, containment of risk is dependent on the actions, or lack thereof, of human beings. The greatest consequences for the equine industry in the U.S. would be if either African horse sickness or Venezuelan equine encephalitis were introduced or re-introduced into the country. Were even one case to occur, it would result in a trade embargo on all horse exports for a minimum of two years. We all know what this industry is worth, not least as one of the few labor-intensive ones that remain. Sometimes one has to err on the side of conservatism. What's at stake is too great.”

First and foremost, Timoney remains animated by a deep respect for the species that has captivated him for decades. After all, there is no more privileged insight into the inner spirit of the Thoroughbred than the relationship of physician and patient. While he has a pragmatic wariness of their unpredictability on occasion, having taken the odd kick in his time, he marvels at their beauty, spirit and performance potential. “The intensely competitive spirit they can have is unequalled among domestic species,” he says. “Horses are such noble creatures. It's easy to see how over millennia, the horse has been the subject of magnificent masterpieces of art and sculpture.”

That this mystique has drawn five decades of diligence and inspiration from Dr. Peter J. Timoney is a profound benediction to our community, though typically he sees it the other way round. “I feel very fortunate,” he stresses. “Both to have been given the opportunity to work in the field I found myself in for the past 50 years, and with an animal species that is a continuing source of wonderment, and an industry that has been so supportive over the years.”