Cases of Lyme disease in Canada are dramatically rising as blacklegged tick populations grow and expand, say health officials who are urging the public to take precautions while enjoying the outdoors this summer.
With warm weather ushering in tick season, experts warn about the risks of infected ticks transmitting Lyme disease, a potentially debilitating infection that can result in heart problems, extreme fatigue and nervous system disorders.
The number of Lyme disease cases is at a record high and expected to keep growing. In 2017, there were 78 cases in Toronto, 987 in Ontario and more than 1,400 in Canada. By comparison, a year earlier there were 23 in the city, 388 in the province and 992 cases nationwide. But because it’s under-reported, some experts say the true number may be tenfold.
“The probability that someone would actually be exposed to a blacklegged tick in the early ’90s was very very low,” says research scientist Robbin Lindsay of the Public Health Agency of Canada, which began tracking Lyme as a nationally notifiable disease in 2009 with just 144 cases. “Now, the situation is very dynamic … The more we look, the more we find.”
In the 1990s, the only known risk area was Ontario’s Long Point Provincial Park. But with climate change, ticks are increasingly moving north from the United States, hitching rides on migratory birds. Now, they’re in Ontario, Quebec, New Brunswick, Nova Scotia, and have moved into Manitoba.