As Canadians are greeted with warmer weather, it’s more than temperatures on the uptick.

Lyme disease is spreading across the country and health officials are predicting a record number of infections for the season after a nearly 50 per cent jump in reported cases last year.

“It’s likely that all provinces are affected with this,” said Dr. Isaac Bogoch, an infectious disease specialist with Toronto General Hospital, on CTV’s Your Morning on Wednesday. “There’s just more and more cases of Lyme usually along the southern border of Canada, but we’ve seen a lot in Nova Scotia, Ontario, Manitoba, B.C.”

The number of cases has increased from just 144 in 2009, to nearly 1,500 in 2017, according to government data. It’s not clear what is causing the spread, though researchers have suggested a number of factors may play a part, from birds carrying ticks around the country to global warming providing warmer temperatures for the bugs to thrive.

The Borrelia burgdorferi bacteria that causes Lyme disease isn’t the only disease-causing agent many Canadians are being warned to beware of this year. Blacklegged ticks can carry other diseases too, including Borrelia miyamotoi and Powassan disease. And the mosquito-borne West Nile virus remains of concern.

The increase in Lyme disease doesn’t mean Canadians must live in fear of the outdoors. “We can’t live in hermetically sealed packages,” said Bogoch. “Enjoy life. Go outside.”

But anyone adventuring into areas where ticks and Lyme are known to be should be armed with the bug spray and knowledge to prevent infection.


Lyme disease has a number of identifiable symptoms, from fever, chills, headache, joint and muscle pain, joint swelling, fatigue, and facial paralysis, but its signature is the bullseye rash, formally called Erythema migrans, which appears at the site of a tick bite about three to seven days later.

“It’s kind of like the homerun for Lyme disease diagnosis,” said Bogoch. “It looks exactly like a target. It’s red, and it’s got a central dot, a little pale area around it, and then another red circle around that.”


Bogoch said it’s a good idea to do a head-to-toe “tick check” with a friend after going outside in buggy areas, because ticks are sometimes difficult to spot. They can be 2 millimetres at the smallest. A tick check is simple: look for a tick on the body.

“They like the areas under the arms. They like the areas on the back, little nooks and crannies,” he said. “Look in the hair, look on the back, places that we might not initially recognize a very small tick.”


The longer it stays lodged in the skin, the more likely it is to pass on Lyme disease, a process that can take up to two days. While there is an assortment of other tools suggested every season, tweezers are the best bet for removal.

“If you go online, you’ll see a bunch of ridiculous things like using a lighter and stuff like that — no,” said Bogoch.“(Ticks) actually cement their head underneath the skin, so it should be removed very, very carefully to make sure that there’s no parts left underneath the skin.”

Using tweezers with a fine tip, grab the tick as close to the skin as possible, steadily and gently pulling upwards. “Try not to twist or crush the tick,” reads a government webpage about Lyme disease, since that could cause the “mouthparts” of the tick to remain lodged in the skin.

But Bogoch says we have the power, or at least the insect repellent, to reduce the risk while exploring the outdoors.

“We can prevent all of these — tick bites, mosquito bites — by really putting on bug spray,” he said. “We have to go outside and enjoy the summer, because summer is so precious here in Canada.”