This is a summary written by members of the CITF Secretariat of Canadian Blood Services’ February 2023 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.
The latest CITF-funded seroprevalence report from Canadian Blood Services showed that seroprevalence due to natural infection was 77.6% at the end of February. This estimate was slightly higher than the 76.7% estimate recorded in January 2023. The youngest donors, aged 17 to 24, continued to have the highest seropositivity due to infection compared to other age groups. Self-declared racialized donors continue to have higher seroprevalence due to infection than white donors.
Key findings:
- Donors aged 17-24 years had the highest rate of infection-acquired seroprevalence compared to other age groups at 88.4%. Seroprevalence among those aged 60+ was 64.9%.
- The seroprevalence rate increased in the 17-24 and 40-59 age groups compared to January.
- Self-declared racialized donors continued to have higher infection-acquired seroprevalence compared to white donors: 83.5% vs 75.9%. Indigenous blood donors had a seroprevalence of 77.7%, while Asian-identifying blood donors had a seroprevalence of 84.3%.
- Infection-acquired seroprevalence among the most materially deprived populations continued to be higher than for the least materially deprived: 79% and 76.8%, respectively.
- Anti-spike antibodies (due to vaccination or infection or both) were present in all blood donors and most age groups saw an increase in anti-spike concentrations. However, February 2023 saw a slight decrease in anti-S concentrations among older age groups.
Conclusion
The latest report builds on the mid-February 2023 report and includes samples from 31,775 unique donors over the age of 17 who donated blood between February 1st and February 28th, 2023, across Canada, excluding Quebec, 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.