SurveillanceMay 30, 2026

Lyme disease in Canada, 2024.

The Public Health Agency of Canada (PHAC) reported 5,809 confirmed Lyme cases in 2024 — a national rate of 14.1 per 100,000 people. That’s on par with the rate over the past several years, after a sharp climb through the late 2010s. Below: where it hit, when it peaked, and who got it.

Headline number

5,809 cases

The 2024 total is roughly in line with 2023 and well above the 2,025 cases reported in 2017. Year-over-year growth has slowed as the blacklegged tick’s range stabilises in already-affected regions — but it continues to push north and west.

Where

By province.

Ontario contributed nearly half the national total in absolute terms. Per capita, Nova Scotia continues to lead Canada by a wide margin — reflecting the well-established blacklegged tick populations across the province.

Approximate per-province totals reflecting PHAC’s reported ranking. Exact figures from the PHAC 2024 annual release.

When

By month of illness onset.

June and July combined accounted for nearly half the year’s cases — the same window when blacklegged nymphs are at peak activity. The shoulder months of May and August carry most of the remainder.

Who

By age group.

Lyme disease tends to peak in older adults — the 50–69 age group accounted for nearly 40 percent of 2024 cases. There’s also a noticeable bump in younger children, reflecting kids’ outdoor exposure during peak nymph season.

What this means

For 2025 and beyond.

Three takeaways:

Lyme is a Canadian disease now. Five thousand confirmed cases a year, every year, is the new baseline. Anyone who spends time outdoors in southern Ontario, southern Quebec, Nova Scotia, or New Brunswick should treat tick checks like sunscreen.
The shoulder season matters more than people think. May and September each contribute hundreds of cases. People who let their guard down once school starts miss a real window.
Older adults are the largest case group.Tick-borne disease isn’t a young-hiker problem — it’s a gardener-in-their-sixties problem too. Yard exposure counts.

More on Canadian Lyme.

Headline figures from the Public Health Agency of Canada (PHAC) 2024 annual surveillance release for Lyme disease and other tick-borne diseases, published January 2026 at health-infobase.canada.ca. Per-province and per-month figures shown here approximate the published ranking and seasonality; the official tables should be consulted for exact counts.

Last reviewed May 30, 2026

General information only — not medical advice. In an emergency, call 911. Read the full disclaimer.