Tick-Borne Disease Expands Into New Parts of Canada, Raising Public Health Concerns

Toronto, June 1, 2025 — Tick-borne illnesses, particularly Lyme disease, are spreading into previously unaffected parts of Canada, triggering growing concern among public health experts. The increase is attributed to changing climate conditions, including warmer winters and longer tick activity seasons.

Experts have confirmed a noticeable expansion of black-legged ticks (commonly known as deer ticks) into new areas such as parts of Ontario, Quebec, Nova Scotia, and British Columbia. These regions were once considered low-risk but are now reporting increasing numbers of tick encounters and Lyme disease cases.

According to recent health data, Ontario recorded 1,865 confirmed Lyme disease cases in 2023, a sharp rise compared to 451 cases in 2015. Health officials link this uptick to the northward movement of ticks and to climate change facilitating their survival in cooler environments.

Public Health Agency of Canada (PHAC) officials have issued alerts advising Canadians to take preventive measures. These include using DEET-based repellents, wearing long-sleeved clothing and pants in grassy or wooded areas, and conducting thorough body checks for ticks after outdoor activities.

Pets are also at risk, with veterinarians urging owners to implement tick prevention routines for their animals. Tick bites can lead to Lyme disease in both humans and animals, causing symptoms ranging from fatigue and fever to more serious neurological complications if untreated.

Meteorologists and environmental health scientists agree that this trend reflects broader ecological shifts tied to climate change. Warmer average temperatures, shorter winters, and an increase in vegetation have created favorable habitats for ticks in previously colder regions.

The federal government is collaborating with provincial health departments to expand tick surveillance programs and enhance public awareness campaigns. Citizens are encouraged to report tick encounters through regional health portals and stay informed through updates provided by PHAC and local health authorities.

The ongoing expansion of tick-borne illnesses underscores the urgent need for coordinated public health responses, long-term planning, and community education to limit the impact on Canadians.