This is a summary, written by members of the CITF Secretariat, of

Germain M, Lewin A, Bazin R, Dieudé M, Perreault J, Boivin A, Grégoire Y, Renaud C. Cohort profile: A Quebec-based plasma donor biobank to study COVID-19 immunity (PlasCoV). medRxiv. 2022 Nov 11. doi: https://doi.org/10.1101/2022.11.09.22282156.

The results and/or conclusions contained in the research do not necessarily reflect the views of all CITF members.

CITF-funded researchers at Héma-Québec, led by Drs. Marc Germain and Dr. Renée Bazin, published a preprint, not yet peer reviewed, reporting on the characteristics of the plasma donors whose samples are used to study COVID-19 immunity in Quebec. The 15,502 plasma samples collected in its COVID-19-focused biobank are representative of the general population, ranging in age from 18 to 84, with nearly a 50/50 split between males and females. The PlasCoV biobank, funded by the CITF, was established in April 2021 by researchers at Héma-Québec to better understand infection-acquired and vaccine-induced immunity to SARS-CoV-2.

Key points:

  • As of January 2022, there were 86,229 plasma samples from 15,502 regular healthy donors (age range=18-84 years, female %=49.7%), for an average of 5.6 donations per donor.
  • Nearly two thirds (65.6%) of donors made at least two donations, thereby allowing for longitudinal analyses. Many donors provided samples pre- and post-vaccination (3061 [19.75%]), while a small group provided samples pre- and post-infection (131 [0.85%]). A forthcoming seroprevalence study is underway to compare anti-N responses pre- and post-infection in order to estimate the incidence of recent infections in the context of the Omicron wave.
  • Serosurveys conducted using biobank samples show that the anti-N antibody response wanes rapidly. Up to one third of previously infected donors no longer had anti-N antibodies after six and a half months.

Researchers highlighted the importance of the longitudinal nature of the biobank, which provides better insights into SARS-CoV-2 immune responses to inform public health officials, especially those in Québec.

Ten blood centers are designated to collect biobank-dedicated samples and the donor cohort is representative of donors living in urban and suburban areas throughout Québec.