Ticks with Lyme disease have made Hamilton home
Black-legged ticks are showing up, but risk of infection is low
Hamilton’s public health department is working on a tick management strategy after most of the city was designated as an “estimated Lyme disease risk area.”
Black-legged ticks — the kind that can carry the Lyme disease bacteria — have now established a home here.
“They are going through their life-cycle in our area, rather than just being dropped off (by animals and birds),” says Connie DeBenedet, Hamilton’s acting vector-borne diseases manager. Public health says the overall risk of human infection remains low, but it is urging the public to learn more about ticks.
A 20-kilometre Hamilton radius of all parts of the city — except eastern parts of Stoney Creek and Glanbrook — is now a Lyme risk area.
For Lyme disease to be a human risk, however, the tick must be of the blacklegged kind, must have the Lyme disease bacteria, and feed on you for at least 24 hours, says DeBenedet.
Not all blacklegged ticks carry Lyme disease.
While DeBenedet says ticks are most commonly found in wooded and tall grass
areas, Flamborough veterinarian Jennifer Merry, of Clappison Animal Hospital, says anecdotally that “even people in urban Waterdown are finding ticks on them after just mowing the lawns.”
“It’s surprising to us. We thought it would just be on people and dogs walking the Bruce (trail),” she said. “My husband was changing tires in our driveway and he got a tick . ... The birds are moving them around.”
Merry says her clinic has seen a dramatic increase in ticks being brought in for identification and in people bringing in their dogs and asking staff to remove ticks from them.
“We used to see one or two ticks a year, but about three years ago, the numbers started to go up.”
The clinic now sees four to five cases a week.
“The numbers are definitely skyrocketing. We get a lot of sandwich bags with ticks in them. We have a lot of blacklegged ticks.”
Public health is working on a management plan it hopes to have ready in the fall, to lower the risk of residents contracting Lyme disease.
“Unfortunately, ticks are very hard to control,” says DeBenedet. “There are only two pesticides approved in Ontario. They are not very effective and the concern is they could affect pollinating
insects. It’s better to use an integrated pest management plan.”
DeBenedet said the plan includes keeping city grass manicured at frequently used parks and sports fields.
With black-legged ticks being very tiny — some are the size of a poppyseed — the good news is they die easily in sunny areas on a typical field, she said.
“Ticks like to hide in tall grass and under leaf litter in cool and shady areas.”
DeBenedet advises people to keep themselves and pets on walking trails and avoid walking through heavily wooded areas where the risk is greater.
Finding a tick on you or your dog can be quite frustrating, DeBenedet admits.
“We find hundreds and hundreds of American dog ticks.”
They are a nuisance, but do not spread disease. The problem is ticks are very small, so it has been hard to tell the American dog ticks from the black-legged deer ticks, she adds.
The city has posted signs showing the difference between the two in busy city parks and walking trails, she said.
In 2017, residents brought in 892 ticks — 78 of them were blacklegged, and of those, seven tested positive for Lyme disease, she said.
DeBenedet expects the numbers to grow slightly this year and afterwards, to continue to grow over time.
Rosa da Silva, McMaster University assistant biology professor, says it is important for people to be aware that Lyme diseasecarrying ticks are here to stay — partly because climate change bringing warmer weather has caused them to spread.
“But it’s not a public health emergency. It’s just a cautionary set of behaviours we need to take up as we enjoy the outdoors.”