ONTARIO — Black-legged tick territory appears largely unchanged in Ontario this year, based on the latest information from the province, although the blood-sucking species has turned up in one new corner of Eastern Ontario.
Public Health Ontario’s recently released 2023 Lyme disease risk map adds a new black-legged tick zone in the northeast area of the City of Kawartha Lakes. Overall, Ontario’s confirmed tick zones continue to form an almost uninterrupted band along the St. Lawrence Seaway and through to the heavily populated west end of Lake Ontario.
Each zone — or estimated risk area — is calculated as a 20 km radius from the centre of a location where at least one black-legged tick was found through drag sampling between May and October in the previous year.
Black-legged ticks may carry Lyme disease bacteria, and whatever the annual mapping exercise might show, Public Health Ontario warns that the species can be encountered almost anywhere in the province.
Black-legged ticks become active as daytime temperatures rise above 4°C.
While most tick bites are harmless, contracting Lyme disease can be extremely serious — if untreated — and can attack the heart and nervous system. Ontario health units suggest a number of precautions to reduce the risk:
• Dress in light coloured clothing, which makes adult ticks and nymphs (small stage of the tick) easier to see when they are on you (because of their darker colour)
• Remember to do a tick check when returning indoors
• Thoroughly check your body for ticks and nymphs and promptly remove and dispose of them. If possible, have someone check you from behind.
• Take a quick shower to help remove any unattached ticks.
• Putting clothes in a hot dryer for several minutes has been found to kill ticks.
Tick specimens are not used for diagnosis of disease and are no longer accepted at Ontario health units.
