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Lyme Disease

Recent Notices

Lyme disease is a serious illness caused by the bite of infected blacklegged ticks. Ticks are small, ranging in size from a poppy seed to a pea. The size of the tick varies depending on its age and whether it has fed recently.

Lyme disease symptoms can differ from person to person with varying degrees of severity. If you have symptoms, see your health care provider right away. The earlier you get a diagnosis, the greater your chances are for a successful treatment.

In Canada, blacklegged ticks are found in forested and overgrown areas between the woods and open spaces. Remember, it is possible to be bitten outside of these areas as tick populations are expanding. As such, Canadians should take precautions to reduce the risk of tick bites.

Watch this video to learn more about Lyme diseaseExternal Link.


Causes of the disease, how it's spread, and where it's found.


Main symptoms, what to look for and what to do if you become ill.


What the risks are and who is most at risk.


How the disease is diagnosed and treatment options.


How the disease can be prevented.


How the disease is monitored.

Health Professionals

Information for Health Professionals.

Reports and Publications

Reports and publications related to the disease.