Ticks are moving northward, spreading across Ontario and forcing public health agencies to help people deal with the threat of infections such as Lyme disease — often for the first time. Populations have exploded over the past several years in southern and eastern Ontario and into Quebec, as climate change makes those regions more attractive to ticks. Now another one is working its way across northwestern Ontario, infesting places like Rainy River and Thunder Bay.
“Twenty years ago it wasn't a problem at all,” says Ken Deacon, entomologist and coordinator of the vector-borne disease unit at Thunder Bay Public Health. “We're assuming it's going to get worse.” Last year his unit received 800 ticks in the mail, sent by residents who wanted to know whether they were at risk for Lyme disease — which starts with headaches, fever, and chills, but if left untreated can cause neurological and cardiac disorders.
Information is crucial during a tick infestation. Ticks bite their human hosts then bury their heads in the skin, hanging on and drinking blood for several days. If one is found within 24 hours of attaching, it can be safely removed before it has a chance to transmit Lyme disease. But humans may not notice they’ve been parasitized — ticks release an anesthetic when they bite — so those in infested areas must check themselves every day.
“It's all part of a daily routine. It's like you wash your hands before dinner, you check for ticks when you come in from outside,” Deacon says. “It's a matter of changing behaviour, but I think changing behaviour is probably the hardest thing you can attempt to do.”
The Public Health Agency of Canada started tracking the tick expansion in 2003, when the arachnids’ Ontario habitat was limited to Point Pelee, Long Point, and Turkey Point — all hotspots for migratory birds that carry ticks from place to place.
“The number of ticks that are coming in on migratory birds has increased. But at the same time we have identified that there is a very clear geographic pattern,” says Nicholas Ogden, senior research scientist at Public Health. “The warmer places over the past few decades have been the first to acquire tick populations and the emergence of these tick populations has occurred at a time which is consistent with it being driven by recent climate warming.”
The blacklegged tick (also known as the deer tick) is the most dangerous: it’s the one that carries Lyme disease. Other ticks may carry diseases other than Lyme, but early detection and proper removal are vital for all species. Those things are easy to do; public health agencies’ biggest challenge is convincing people to do them.
Thomas Mather, director of the University of Rhode Island’s Tick Encounter Resource Center, designed a program to help people become, as he brands it, “TickSmart.” Directives are simple: perform regular checks, remove ticks using pointy tweezers (which can get right at the head) rather than flat ones (which merely crush the body, leaving the head intact), and repel them with permethrin-treated clothing.
“We felt that we have good answers for solving people's tick problem, but what seems to be lacking is implementation,” Mather says. “If you start having misinformation become predominant during the time when people are first taking an engaged approach to it, that sticks and you have trouble getting rid of it. You want to be Johnny-on-the-spot with appropriate information, and you want to do everything you possibly can to ensure people have that information.”
Mather has made cards to put in the shower that show what body parts ticks like to feed on (such as the underarms and groin, where they thrive in the heat and moisture), as well as cards to put near the toilet, reminding people to check for ticks between their legs. Health units in areas like Thunder Bay face an uphill battle getting people to perform such checks regularly.
That’s part of the work Deacon is doing. In addition to identifying ticks and evaluating threat levels, he’s an educator.
“The more you talk about it the more people are aware that there is a problem — and hopefully the more precautions they'll take,” Deacon says. “The ticks are here. There's no way we're going to eradicate ticks. So if they're here then we have to learn how to live with them and to prevent disease.”
Deacon has a personal connection to Lyme disease — his wife contracted it seven years ago. While there was a nascent awareness of ticks in the region then, the threat they posed was not widely understood. And the telltale bullseye rash that tends to form around the spot a Lyme-carrying tick has bitten didn’t appear in her case.
“If you don't have that, then it's not on the checklist for MDs to go through,” Deacon says. “Then it's a really difficult disease to deal with.”
Deacon’s wife was misdiagnosed. But soon her initial symptom — an ice-pick headache, for which she was given only painkillers — evolved into Bell’s palsy, paralyzing one side of her face. It wasn’t until the bloodwork came back that doctors correctly diagnosed her with Lyme disease and administered antibiotics.
“When I was doing my undergraduate in entomology what I wanted to be was a medical entomologist. The professors, snickered and thought, in Canada, what are you talking about?” Deacon says. “Now it looks like medical entomology is an area of concern in Canada.”
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