Dogs face an uptick in Lyme disease
Warming climate brought ticks north, veterinarian says, and they are here to stay
Every year when Teresa Greaves visits Rondeau Provincial Park in southwestern Ontario, she ends up picking off a handful of ticks from her two dogs.
But this past fall, the numbers were out of control.
“I picked probably 100 ticks off between the two of them over the course of the week,” Greaves said. “It’s definitely a lot more than we ever had found on them before.”
When she got back and took her dogs to the vet, the four- and fiveyear-old Rottweiler mixes named Padre and Tango both tested positive for Lyme disease. Just as the number of human Lyme disease cases has risen in recent years, there has also been a sudden uptick in pets, according to veterinarians in the GTA.
Dr. Kathleen Alcock of the Ashbridges Bay Animal Hospital in the beaches said her clinic is seeing more dogs with ticks than ever before.
“It was novel,” she said. “Now it’s like, oh my god, another dog with a tick, or a tick bite. There’ve been dogs in our practices that have had upwards of 11 ticks when they bring them in to be removed. The tick bite itself is not such an issue, it’s the fact that (some) ticks are carrying Lyme disease.”
Much of Toronto, as well as parts of York and Durham regions, are in risk areas for Lyme disease, according to a 2017 map by Public Health Ontario, which defines a risk area as a 20kilometre radius around where ticks have been found.
Alcock said four dogs have tested
“This is the new black. Now that the ticks are here . . . I think we’re going to see a lot more Lyme disease.” DR. KATHLEEN ALCOCK ASHBRIDGES BAY ANIMAL HOSPITAL
positive for Lyme disease at her clinic since March. The norm at this point of the year? “None, zero,” she said. “It’s been coming for a while,” Alcock added. “It’s very obvious that the warming of the climate is bringing the ticks north. The hotbed for ticks and Lyme used to be New York state. It’s just coming around to Toronto.”
Alcock said it’s important to note that it’s impossible for a Lymepositive dog to pass on the illness to its human family.
“It’s way easier to prevent ticks in dogs than it is in people,” Alcock said. “I give one pill every12 weeks and the dog is free of ticks for the entire summer.”
There were 841 human cases of Lyme disease in 2016 across the country, compared with 144 in 2009. The number of cases has risen in Ontario from 44 in 2005 with 343 in 2016.
Dr. Jennifer Kyes of the Mississauga Oakville Veterinary Emergency Hospital said “active” dogs that spend a lot of time outdoors in wooded and rural areas face the highest risk of coming into contact with Lyme-carrying ticks.
“It is a big concern because it can to lead to some significant illnesses outside of a fever and just having swollen joints,” she said. “It can lead to kidney failure and other much more significant diseases (in pets).”
Kyes recommends a preventative vaccine for dogs, which can reduce the severity of the disease even if it is still contracted.
Alcock said that in order for a tick to pass on the Borrelia organism, which causes Lyme disease, it needs to be in contact with a dog for at least 18 hours.
“What our medications are meant to do is when the tick bites, it dies,” she said. “You will still see potential for tick bites and you may even find . . . a dead tick on a dog, but there’s no disease transfer.”
Ticks can survive until temperatures drop to 4 C and remain there consistently. Below four degrees, they can’t bite, Alcock said.
Still, she expects to see them back next year and in high volume.
“It’s going to be a cycle,” Alcock said. “This is the new black. Now that the ticks are here, I think they’re going to stay and I think we’re going to see a lot more Lyme disease in people and in dogs.”