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revised Friday February 17 2023

Lyme Disease | West Nile Virus | Eastern Equine Encephalitis



Who is at risk

Where you live, work or travel can affect your chances of getting Lyme disease. Ticks thrive in wooded areas, leaf litter and in long grass. People who spend time in areas where there are infected ticks are most at risk.

Risk areas in Ontario

Borrelia burgdorferi (the bacteria that causes Lyme disease) has been found in blacklegged ticks in these Ontario regions:

  • Long Point Provincial Park
  • Turkey Point Provincial Park
  • Rondeau Provincial Park
  • Point Peele National Park
  • Prince Edward Point National Wildlife Area
  • St. Lawrence Islands National Park
  • Wainfleet Bog Conservation Area (Niagara)

While these areas in Ontario are considered the highest risk for Lyme disease, ticks can attach to migratory birds, and be moved to areas where we wouldn’t normally expect to find infected ticks. Changes to our climate - such as warmer seasons - could also lead to more blacklegged ticks in other parts of the province.


Lyme disease is found in temperate forested regions of Europe and Asia and in the northeastern, north central and Pacific coastal regions of North America.

If you’re planning a trip within North America:

If you are planning on travelling to areas that are considered high risk for infected ticks, you should take the following precautions:

  • Frequently apply insect repellent containing DEET to skin and clothing.
  • After you spend time outdoors, check your skin and your children’s skin (body and scalp) carefully for ticks.
  • Promptly remove any attached ticks.
  • Wear long-sleeved shirts that fit tightly around the wrist and long-legged pants tucked into socks or shoes.
  • Wear light coloured clothing to make ticks easier to spot.

Women who are pregnant

Although rare, Lyme disease can cause a woman to miscarry or deliver a stillborn child. So pregnant women should especially avoid tick bites.


Death caused by Lyme disease is rare. However, undiagnosed Lyme disease can develop into chronic symptoms and conditions that can be hard to treat.

Treatment of Lyme disease is highly effective if it is diagnosed early. Several antibiotics are available to treat Lyme disease. Most cases can be cured over 2-4 weeks of treatment with doxycycline, amoxicillin, or ceftriaxone.

People with certain heart, brain or nervous system ailments might need intravenous treatment with penicillin or ceftriaxone.

Later stage treatment

People who are diagnosed in the later stages of the disease can have persistent or recurrent symptoms and might need to be on antibiotics longer than people diagnosed in the early stages.

Sometimes the first round of treatment doesn’t work (treatment failure), so a person infected with Lyme disease needs to be re-treated. Treatment failure happens more often to people in the later stages of a Lyme disease infection.

* Adapted from the Public Health Agency of Canada’s Lyme Disease Fact Sheet

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Revised: Friday February 17 2023

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