Ontario Vector-Borne Disease Tool

The Ontario Vector-borne Disease Tool offers comprehensive surveillance data on vector-borne diseases (VBDs) in Ontario. This interactive resource allows users to explore trends in human cases for anaplasmosis, babesiosis, Lyme disease, Powassan virus infection, and West Nile virus illness, as well as surveillance data for mosquitoes, and blacklegged tick established risk areas. VBD data are available across multiple dimensions, including year-to-date and weekly case counts, mosquito and tick species distribution, and positive surveillance results.

This tool is updated weekly for all human VBD cases. Mosquito data will be update weekly during the mosquito season (May–October).

Historical West Nile virus data can be provided upon request. Visit PHO’s Data Requests page for more information.

How to Use The Tool

The tool is best viewed on desktop or tablet.

To learn how to navigate the tool, see our User Guide.

To see information on data sources, methods, caveats,  glossary of terms, and more, see our Technical Notes.

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Contact the Department

Communicable Disease Control

Communicable.DiseaseControl@oahpp.ca

Published 5 June 2025