This is a summary written by members of the CITF Secretariat of Canadian Blood Services’ mid-December 2022 report of data gathered from blood donations. The results and/or conclusions contained in the research do not necessarily reflect the views of all CITF members.

Canadian Blood Services data suggest 73.3% of donors had infection-acquired antibodies by mid-December 2022 – slightly higher than the 71% Canadian Blood Services estimated at the end of November. The 17-24 age group continued to see the biggest jump among blood donor groups, with about 88% seropositivity due to infection in mid-December, up from 84.6% two weeks earlier.

Key findings:

  • Infection-acquired seroprevalence increased over the reporting period from 70.8% in the last week of November, to 72.1% in the first week of December, to 73.3% by mid-December.
  • Consistent with previous surveys, donors aged 17-24 years had the highest seroprevalence rate compared to other age groups: 87.7% in the week of December 8-15, compared to 84.6% at the end of November.
  • Compared to the last week of November, the infection-acquired seroprevalence rate increased in all provinces except Manitoba, New Brunswick, and Nova Scotia.
  • Self-declared racialized donors continued to have higher seroprevalence compared with donors considering themselves white: 81% of racialized donors had infection-acquired antibodies by December 15th, compared to 71.6% of white donors.
  • Not much difference was observed in infection-acquired seroprevalence between the most materially deprived populations and the least materially deprived populations. Indeed, while infection-acquired seroprevalence was 73.9% among the most materially deprived by mid-December, it was 73% among the least deprived by mid-month, suggesting the gap has closed.
  • Infection-acquired seroprevalence observed between the most socially deprived populations and the least socially deprived populations was 71% and 75.4%, respectively, in the week of December 8-15.


The latest report builds on the end-November 2022 report and includes samples from 17,061 unique donors over the age of 17 who donated blood between December 1st and 15th across Canada, excluding Quebec and the Territories.

It should be noted that individuals who choose to donate blood are generally in good health and are more likely to live in populous urban areas. Percentages were adjusted for test characteristics and population distribution.

Explore our interactive webpage, updated every month, featuring the latest aggregated data gathered by the Canadian Blood Services and Héma-Québec on SARS-CoV-2 seroprevalence in Canada.