TORONTO -- Climate change has caused tick populations to increase and spread into urban areas throughout Canada, scientists say.
Cases of Lyme disease from tick bites have increased in the last decade. Heath MacMillan, a biology professor at Carleton University, told CTV’s Your Morning this is because climate change has impacted the movement and spread of tick populations, causing them to move out of their traditional habitats in forests, along trails and in rural environments, into urban centres.
“This year we had a particularly mild winter, especially in southern Ontario and also a wetter winter,” MacMillan said in an interview on Friday “This is something that is happening more and more frequently. We’re having winters like this because of climate change, where we’re not getting as much snow cover, we’re not getting as much constant low temperatures, and this is something that makes ticks survive better in the winter which means we have more in the spring.”
Health Canada reported 2,636 cases of Lyme disease in 2019 compared to 144 cases in 2009.
Blacklegged ticks, the species that carries Lyme disease, are found in forests, wooded areas and on shrubs, leaves and long grass.
However, with milder weather, some ticks have been able to survive the winter, which has led to an increase in population and habitat spreading.
“People are tending to find them now in more urban areas rather than just in rural areas or trails, because populations grow they end up in different areas,” MacMillan said. “They can also evolve to change over time because they have a relatively short life cycle.”
Over 88 per cent of the reported cases of Lyme disease in 2016 were from Ontario, Quebec and Nova Scotia, according to Health Canada.
Despite this, MacMillan says people shouldn’t stop enjoying the outdoors out of fear of being bitten by an infected tick. However, he says Canadians should be cautious and take certain measures to protect themselves.
“The biggest thing we can do is to wear long pants, long sleeve clothing. Tics can’t jump, they climb onto us from vegetation low-down, so essentially if you’re wearing stuff that covers your skin, they are less likely to get access to your skin and to bite you,” MacMillan said.
Ticks practise behaviour known as “questing,” where the insect uses its back legs to hang onto low bushes or grass, allowing it to stretch out its front legs and attach onto whatever passes by.
“Another big recommendation is to check yourself after you’ve been outside to see if you find any ticks,” MacMillan says. “Look for the warmest places on your body, which tend to be places like our armpits, between our legs, areas that are generally warmer. That’s where they like to bite.”
Public Health Canada also recommends using insect repellent, putting clothes in the dryer after being outdoors and maintaining one’s property to prevent tick infection.
Pet owners should also check their pets for ticks, MacMillan said.
“In terms of taking pets out for a walk, there is great medication available from vets that can prevent dogs, for example, from getting bit by ticks. Essentially, it’s a toxin that the ticks, when they bite, they die,” MacMillan explained. “That’s great because it actually not only protects your dog, but it also protects you because if the tick is dead it can’t come off the dog and onto you.”
If you are bitten by a tick, MacMillan says the arachnids can be removed at home.
“You can pull them off with tweezers. If you get them within 24 hours the chances of them transmitting Lyme disease is very low,” MacMillan said.
Health Canada recommends pulling the tick straight out of the skin without crushing the insect helps ensure that bacteria from the tick does not enter the bloodstream.
Once ticks are removed, they should be placed in a secure container and local public health units should be contacted to help keep track of where ticks are located.
MacMillan said it is important to be educated on how to stay safe around ticks.
“We tend to have an innate fear, kind of an internal fear in general about insects and arachnids…” says MacMillan. “But they’re part of life, they're part of the wonderful world of biology that’s out there and I think being aware of them and being careful and knowledgeable about what the risks are and how to avoid the worst consequences is really the best thing we can do.”
