Ticks and Lyme Disease: Information for Healthcare Providers

Lyme disease is caused by the bacterium Borrelia burgdorferi, transmitted to humans through the bite of an infected blacklegged tick. Lyme disease is designated as a disease of public health significance and is reportable under the Ontario Health Protection and Promotion Act.
Prevention, early detection and treatment are essential to reduce the burden of Lyme disease. Health providers should be familiar with:

Important information about testing:

In September 2021, The National Microbiology Laboratory stopped accepting blacklegged ticks for bacterial testing of Borrelia burgdorferi as part of the passive tick surveillance program. 
Although there remain private laboratories that test ticks for Borrelia burgdorferi, laboratory testing of the specimen should not be used to diagnose Lyme disease in humans.

Estimated Risk Areas and Trends

The incidence of Lyme disease reported in Ontario and Canada has increased in recent years. The rise is attributable to climate change and other changes driving rapid geographic expansion of blacklegged ticks and supporting conditions suitable for B. burgdorferi. Blacklegged ticks infected with the pathogen causing Lyme disease are known to be present in Wellington-Dufferin-Guelph and neighbouring areas.

Estimate Risk Areas

According to Public Health Ontario, although estimated risk areas have been mapped, it is important to note that blacklegged ticks feed on and are transported by migratory birds and there is consequently a possibility of encountering an infective blacklegged tick almost anywhere in Ontario:

Lyme Disease Trends

Management of Tick Bites

Tick removal

Tick species identification

  • To have the tick species identified and support local surveillance efforts, please use WDGPH’s online tick photo submission form.
    • WDGPH aims to provide a response within 1-3 business days as often as possible (and often responds in under 2 business days).
  • Healthcare providers should consider timelines associated with post-exposure prophylaxis (i.e. PEP can be offered within 72 hours of the tick being removed) when determining whether to wait for results from tick species identification services.
  • If identifying the tick in your office, please consult TickEncounter’s:

Clinical guidance for management of tick bites

Lyme disease is caused by the bacterium Borrelia burgdorferi and is transmitted to humans through the bite of an infected blacklegged tick. According to Health Canada, the bacterium is transmitted by infected nymphs and adult females. For further information on this, visit: Health Canada: Lyme Disease for Healthcare professionals.

Clinical guidance documents:

Additional clinical resources


Reporting Requirements for Physicians

Lyme disease is designated as a disease of public health significance in Ontario. Suspected or confirmed cases of Lyme disease are reportable to local public health under the Ontario Health Protection and Promotion Act and must be communicated to Wellington-Dufferin-Health Public Health.

Patient Resources

Avoiding tick-bites, making ticks checks part of routines, and early detection can decrease the risk of Lyme disease. Clinical management should include patient education on these items. The following resources can be shared:

Additional Resources

Partially adapted from Simcoe Muskoka District Health Unit Lyme Disease webpage for Health Professionals