Seroprevalence studies

What percentage of the Québec population has been infected by COVID-19 since the beginning of the pandemic?

Studies conducted by Héma-Québec in collaboration with the Institut national de santé publique (INSPQ), and in partnership with the COVID-19 Immunity Task Force (CITF), aim to answer this question by looking for virus antibodies in the blood of donors.

An initial study of this type, referred to as a seroprevalence study, was conducted in the spring of 2020, following the first wave of COVID-19. A similar study, in the context of the second wave of the pandemic, was conducted between January 25 and March 11, 2021.

The results are used to measure the progression of immunity in the population. These studies are also used to provide an overview of immunity in the population throughout the vaccination campaign.

Why use blood donors for such a study?

Blood drive activities in Québec make blood donors a representative group of the general population. Héma-Québec was able to conduct this type of study because the organization already had blood samples for each blood donation and the laboratories and expertise to carry out these tests.

Press release of the second study | Results of the second study (PDF, in French only)

Press release of the first studyResults of the first study (PDF, in French only)