Seroprevalence studies

A study funded and led by the CITF, published in CMAJ, found that as of March 2023, over 75% of people in Canada had antibodies due to a SARS-CoV-2 infection.

The latest CITF-funded report from Canadian Blood Services suggests that the 80% mark in estimated infection-acquired seroprevalence among Canadian adults has now been reached.

The latest CITF-funded report from Canadian Blood Services suggests that the 80% mark in estimated infection-acquired seroprevalence among Canadian adults has now been reached.

A CITF-funded study, published in Research Synthesis Methods, found that implementing a natural language processing (NLP) tool for abstract screening in a living systematic review of SARS-CoV-2 prevalence was feasible and beneficial in a real-world context.

A CITF-funded study, published in preprint and not yet peer-reviewed, found that the reporting of SARS-CoV-2 seroepidemiologic studies needs improvement, particularly in providing adequately detailed information about laboratory methods. Researchers showed that there was a median adherence to reporting items of 48% per study, as evaluated via the Reporting of Seroepidemiologic studies—SARS-CoV-2 (ROSES-S) guideline.

In a study now published in Infectious Diseases, CITF-funded researchers from Héma-Québec reported on the development of a novel analytical approach to detect recent SARS-CoV-2 infections based on anti-nucleocapsid antibodies.

Despite 100% of blood donors having vaccine-induced antibodies, infection-acquired seroprevalence continued to rise by the end of October 2022, to 67.3%, up from 63.2% at the end of September.

According to Canadian Blood Services, the infection-acquired antibody rate increased moderately from 65.4% in the last week of September to 66.3% by mid-October, consistent with the continued circulation of Omicron subvariants. Seroprevalence due to infection surpassed 80% among young donors (17-24 years of age) and 70% among the most materially deprived.

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 Renée Bazin, published a preprint, not yet peer reviewed, reporting on the characteristics of the plasma donors whose samples are used to study COVID-19 immunity in Quebec.

Héma-Québec estimates that 62% of Quebecers who donated plasma had acquired antibodies following an infection with Omicron by the end of August 2022.