By Trudy Frisk
“Wood ticks,” once said acarologist John D. Gregson, “are friendly little creatures. You can get quite attached to them!”
Jack would know. He was Canada’s leading expert on ticks and tick-borne diseases. He published more than 100 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 40 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 worldwide.
There are 24 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 explained. “They evolved with their hosts over about 300 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 noted, “B.C. holds the dubious honour of containing the greatest association between one particular species of tick and man, livestock, and pets.”
In 1928, at the request of the local ranchers, a laboratory was established in Kamloops to study the tick. Kamloops was selected because of its ecological diversity and thriving cattle industry. It’s also the wood tick’s ‘heartland.’
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 more than 100 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 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 more than 70 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 aren’t alike. Ticks in B.C. 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 10 per cent of ticks paralyze. “But,” Jack warned, “those that do, can repeatedly paralyze successive hosts.”
The coast tick, which is very different from the Interior tick, feeds on mice and lizards in its early stage and can carry Lyme disease. Its longer mouthparts are quite difficult to remove. Moreover, it seems that, around Shumway and Napier Lakes, between Kamloops and Merritt, a new sub-species is evolving.
Jack’s work at the Lab was ground-breaking. “Not many people were studying ticks,” he remembered. In fact, there were only about 50, widely dispersed worldwide. 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. 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 chuckled.
Kerosene had been the chemical compound used against ticks. When veterinary systemic insecticides were introduced, they 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 arthropod-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.
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?
