Vector-borne Disease Surveillance in Canada, 2023
Download this article as a PDF (586 KB)Published by: The Public Health Agency of Canada
Issue: Volume 52-1/2, January/February 2026: Tick and Mosquito Surveillance in Canada
Date published: February 2026
ISSN: 1481-8531
Submit a manuscript
About CCDR
Browse
Volume 52-1/2, January/February 2026: Tick and Mosquito Surveillance in Canada
Infographic
West Nile Virus
Text description: Infographic
In 2023, 98 cases of West Nile virus (WNV) were reported at a rate of 0.24 per 100,000 population. Forty-six cases developed severe neurologic disease and of these, two died.
Disease rates were highest among males. People 60 years and older had a higher risk of severe disease and death. Case counts in 2023 were lower than the five-year average (n=131).
| Year | Cases | Rate | Rate (Females) |
Rate (Males) |
|---|---|---|---|---|
| 2014 | 20 | 0.06 | 0.04 | 0.07 |
| 2015 | 77 | 0.22 | 0.20 | 0.23 |
| 2016 | 84 | 0.23 | 0.21 | 0.26 |
| 2017 | 189 | 0.52 | 0.41 | 0.63 |
| 2018 | 337 | 0.91 | 0.76 | 1.06 |
| 2019 | 36 | 0.10 | 0.10 | 0.10 |
| 2020 | 162 | 0.43 | 0.41 | 0.44 |
| 2021 | 43 | 0.11 | 0.11 | 0.11 |
| 2022 | 45 | 0.12 | 0.08 | 0.15 |
| 2023 | 98 | 0.24 | 0.20 | 0.28 |
About 6% of cases were likely acquired outside of Canada.
| Province | Cases |
|---|---|
| Alberta | 13 |
| Saskatchewan | 3 |
| Manitoba | 5 |
| Ontario | 58 |
| Québec | 19 |
The earliest reported symptom onset date was June 20 with 83% of cases having illness onset in August and September.
| Month | Cases |
|---|---|
| January | 0 |
| February | 0 |
| March | 0 |
| April | 0 |
| May | 0 |
| June | 2 |
| July | 6 |
| August | 40 |
| September | 45 |
| October | 5 |
| November | 0 |
| December | 0 |
Lyme disease
In 2023, 4,785 cases of Lyme disease were reported at a rate of 11.9 per 100,000 population.
Disease rates were higher among males, people aged 60–79 and, among children, those aged 5–14, compared to similar age groups. The 2023 rate was almost twice the 2022 rate.
| Year | Cases | Rate | Rate (Females) |
Rate (Males) |
|---|---|---|---|---|
| 2014 | 522 | 1.47 | 1.3 | 1.64 |
| 2015 | 917 | 2.57 | 2.16 | 2.98 |
| 2016 | 992 | 2.75 | 2.43 | 3.06 |
| 2017 | 2,025 | 5.54 | 4.44 | 6.45 |
| 2018 | 1,487 | 4.01 | 3.14 | 4.25 |
| 2019 | 2,636 | 7.01 | 5.88 | 8.09 |
| 2020 | 1,617 | 4.25 | 3.71 | 4.79 |
| 2021 | 3,147 | 8.23 | 7.11 | 9.33 |
| 2022 | 2,525 | 6.49 | 5.91 | 7.02 |
| 2023 | 4,785 | 11.9 | 10.15 | 13.67 |
About 4% of cases were likely infected during travel outside of Canada. Cases reported by Alberta, Saskatchewan and Newfoundland and Labrador were travel-related only.
| Province | Cases |
|---|---|
| British Columbia | 28 |
| Alberta | 20 |
| Saskatchewan | 3 |
| Manitoba | 58 |
| Ontario | 1,859 |
| Québec | 652 |
| New Brunswick | 101 |
| Nova Scotia | 2,057 |
| Prince Edward Island | 5 |
| Newfoundland & Labrador | 2 |
Almost half (40%) of all cases with available information had an illness onset in July with 94% having an onset date between May and November.
| Month | Cases |
|---|---|
| January | 19 |
| February | 15 |
| March | 26 |
| April | 39 |
| May | 119 |
| June | 394 |
| July | 845 |
| August | 333 |
| September | 146 |
| October | 95 |
| November | 54 |
| December | 19 |
For more information, visit the Vector-borne Disease Surveillance in Canada dashboard pages: https://health-infobase.canada.ca/?category=Zoonoses.
