JACK GREGSON- A MAN ATTACHED TO TICKS|
JACK GREGSON- A MAN ATTACHED TO TICKS
Story and photos by Trudy Frisk
Jack Gregson reviewing one of his articles on tick paralaysis
"Wood ticks", says acarologist John D, .Gregson, "are friendly little creatures. You can get quite attached to them!"
Jack would know. He is Canada's leading expert on ticks and tick-borne diseases. He has published over one hundred scientific papers, identified and named three species of western ticks and had an eastern boreal forest tick named for him as a tribute to his forty years of contributions to understanding the complex world of tick physiology. His research at Agriculture Canada's Veterinary and Medical Entomology Laboratory in Kamloops , B.C. is known and respected world wide.
There are twenty-four kinds of ticks in B.C. Most are specific to certain birds and animals. "The shrew has its tick, the pika its tick, the squirrel its tick." Jack explains. "They evolved with their hosts over about three hundred million years and they don't like any others. The exception is the Rocky Mountain wood tick which will attach itself to humans and a variety of animals. In addition to transmitting several diseases, it can paralyze and kill its host." Paralysis by different species of ticks has been recorded in a dozen countries around the world, but, Jack notes, "B.C. holds the dubious honour of containing the greatest association between one particular species of tick and man, livestock, and pets."
As far back as 1912 symptoms of paralysis by Rocky Mountain ticks were recorded at McGill University. Between 1900 and 1970 six hundred head of cattle were lost and there were thirty human fatalities. The human deaths were mostly around 1900 when not much was known about ticks. In 1957 three hundred head of cattle in the Nicola Valley were paralyzed.
In 1928, at the request of the local ranchers, a laboratory was established in Kamloops to study the tick, known to have adverse effects on sheep, cattle, humans and dogs. Researchers also studied biting flies, cattle grubs, and cattle lice. Kamloops was selected because of its ecological diversity and thriving cattle industry. It is also the wood tick's 'heartland'.
Jack, who had previously studied black flies and mosquitoes, joined the lab in 1933. He was in charge from 1944-1954, retiring in 1971. Here, at the lab on Mission Flats, he began the research which brought him world-wide acclaim in both medical and agricultural circles. There was strong co-operation between veterinary entomologists and scientists conducting public health studies on diseases communicable to humans from other species.
In order to find a remedy for tick paralysis Jack investigated the method and specific toxins ticks used. He pioneered a means of collecting tick saliva,(by the thimbleful), for analysis. In order to ascertain how ticks could both suck blood and inject saliva, Jack cut the tick's head, about the size of a grain of sand,, into over one hundred slices which were then stained to differentiate the tissues. The resulting slide show, "A Journey Down The Throat Of A Tick", is an example of his painstaking care and precision. He discovered that there were long periods of sucking, broken by intervals of injection of saliva, and that slow administration of the toxin was important for paralysis to take place. Researchers found over seventy components in tick saliva, and noted that paralysis by ticks occurs at the junction of nerves and muscles. If they could identify the individual toxin, the scientists believed they could discover an antidote.
Ticks, which are arachnids, (eight-legged), not insects, crawl up blades of grass or onto bushes and wait there in their quest for a host. When an animal brushes by, the tick catches a ride. All ticks are not alike. Ticks in B.C. will crawl to the highest point, the top of the head, in cattle and humans. Scientists at the Mission Flats Lab advised ranchers to spray their cattle on the backs and tops of their heads. In Alberta, though, ticks may not crawl upward, but attach to the underside of the animal. Ticks in the Nicola Valley in B.C. are more potent than ticks in Alberta. In fact, Alberta ticks rarely cause paralysis. Even in B.C.'s 'hot spots', only about ten percent of ticks paralyze. "But", Jack warns, "those that do, can repeatedly paralyze successive hosts." The Rocky Mountain wood tick doesn't carry Rocky Mountain spotted fever in B.C., but, in Alberta and the U.S, it does.
Jack's 1949 painting of Rose Hill and the grasslands
The coast tick, which is very different to the Interior tick, feeds on mice and lizards in its early stage and can carry Lyme disease. Its longer mouth parts are quite difficult to remove. Moreover, it seems that, around Shumway and Napier Lakes, between Kamloops and Merritt, a new sub-species is evolving.
The earliest tick Jack ever recorded was on January fourth. Usually ticks, most often found on rocky hillsides with southern exposures, are active only in spring. Jack correlates their cycle to the blooming of native plants. "Ticks become active when buttercups come out, peak when saskatoons flower, and are finished by the time chokecherries bloom." Males emerge a few days earlier than females. Only females cause paralysis. They have to feed for four days before they become dangerous and, after mating, they're benign -unable to cause paralysis.
Jack's work at the Lab was ground-breaking. "Not many people were studying ticks.", he remembers. In fact there were only about fifty, widely dispersed world-wide. They corresponded, exchanged papers and met at international congresses in Seattle, Vienna, Nairobi, Geneva and Nottingham.
Tick research has its unexpected difficulties. First, of course, they had to catch their ticks. This meant traveling to good collecting sites and sweeping the vegetation with flannelette sheets. (There was a suggestion that also wearing long flannel nightgowns would hasten collection.) During the Second World War citizens were alert for strange events. Police received a report of suspicious activities around Stump Lake. Turned out to be just the fellows from the research lab gathering ticks. "They thought we were signaling with white flags!", Jack chuckles.
Keeping specimens separated and correctly labeled is essential. Jack often took his children along on tick outings. After one particularly successful day, he noticed how quiet they were in the car going home. Only in the drive-way did he discover that daughter Sally, in the back seat, had patiently pulled the plugs out of all the collecting vials. Barbara, Jack's wife, worried about getting ticks off the kids and out of the car. Jack's chagrined reaction was that all the collecting had to be done again.
Kerosene had been the chemical compound used against ticks. When veterinary systemic insecticides were introduced, the were tested at the Kamloops lab under Jack's direction. Those tests, widely recognized, added to the reputation of both the lab and Jack, himself.
Emphasis was shifting from a search for an antidote, to tick toxin, to preventative methods. Some programs were taken over by other research stations, others were phased out. The Mission Flats Lab at Kamloops closed in 1971.
During his career Jack was invited to address the World Health Organization. He spoke , in the U.S., Canada, the U.K., Austria and Switzerland, to other councils investigating arthropoid-transmitted diseases. He was the U.S. Navy Medical Unit's consultant on parasitic problems in the Middle East. Scientists from Australia and Egypt visited Jack at the Lab in Kamloops and he traveled to Cairo to advise on methods for tick research there.
Upon his retirement colleagues in universities and medical centres, from Alma Ata in Mongolia, to, Israel, Russia, South Africa, Australia and the U.S. praised his innovative work on tick taxonomy, ecology and disease vector capacity.
Jack's 1939 painting of the road to the Mission Flats Lab
Even after retirement, Jack continued to work on the problem of Lyme disease.
He was named a Freeman of the City of Kamloops for his many contributions to his community including co- founding the Garden, Naturalist and Outdoor Clubs.
Jack is also a skilled amateur artist who, in the 1940s, painted alongside A.Y. Jackson of Canada's famed Group of Seven. In 1942 Jack's painting, "Revelation Pass" was judged second-best in show at the Vancouver Art Gallery.
In 2004, at the age of ninety-three, Jack had his first solo exhibit, in the Kamloops Art Gallery. "Mission Flats Road", painted in 1939, is Jack's view of the road he traveled to the Research Lab for nearly forty years. Who would have suspected that the work being done at the end of that quiet, one-lane country road would establish Jack Gregson and the Kamloops Mission Flats Veterinary and Medical Insect Laboratory in scientific circles around the world?
Other articles by Trudy Frisk