General Population
Age-stratified SARS-CoV-2 Serological Prevalence Estimation Using Anonymized Residual Sera Following Delta and Omicron Waves in the Northwest Territories (NWT)
Kami Kandola, University of Calgary & University of Alberta
In the Northwest Territories (NWT) more than 10,000 SARS-CoV-2 infections were reported between March 2020 and March 2022 (the majority of cases were self-reported rapid antigen tests from late December 2021 to March 2022), and over 99,000 vaccine doses were provided to NWT residents by March 2022.
Research summary Results Study website View study on
Canadian COVID-19 Antibody and Health Survey (CCAHS) second cycle
Ron Gravel, Statistics Canada
This second cycle of the Canadian COVID-19 Antibody and Health Survey (CCAHS) aims to better understand the impacts of the pandemic on the health and well-being of Canadians, including the prevalence of chronic symptoms and conditions and the challenges that Canadians may have faced in accessing healthcare.
Surveying prospective population cohorts for COVID19 prevalence and outcomes in Canada (SUPPORT-Canada)
Philip Awadalla, Canadian Partnership for Tomorrow’s Health (CanPath)
Building on Canadian Partnership for Tomorrow’s Health (CanPath), a national population health research platform that follows the health of 330,000 Canadians, SUPPORT-Canada aims to capture data and biologics to help researchers and clinicians determine the factors that contribute to COVID-19 susceptibility and severity.
Research summary Results Study website View study on
Seroprevalence study and cross-validation of high-throughput serological tests conducted by the COVID-19 Immunity Task Force (Héma-Québec)
Marc Germain, Héma-Québec
This study aims to estimate how many people have contracted SARS-CoV-2 in Quebec or have antibodies to the virus due to vaccination. Researchers will do this by determining the prevalence of antibodies in a sample number of blood donors. The study started after the first wave of the COVID-19 pandemic in Quebec.
Research summary Results Study website View study on
The Canadian COVID-19 Antibody and Health Survey (CCAHS)
Ron Gravel, Statistics Canada
Conducted by Statistics Canada, this survey aims to identify how many Canadians have been infected with SARS-CoV-2, the virus that causes COVID-19. Our study is the first to use a nationally representative sample to reflect COVID-19 seroprevalence across Canada at national, provincial, and territorial levels. This study is the first to use a nationally representative sample to reflect COVID-19 seroprevalence across Canada at national, provincial, and territorial levels.
Research summary Results Lab website View study on
Canadian Population Serological Survey Utilizing Antenatal Serum Samples
Deborah Money, University of British Columbia
This study analyzes blood samples from expectant women across the country to help determine the prevalence and spread of SARS-CoV-2 in Canada.
Research summary Results Study website View study on
Canadian Blood Services: Testing for SARS-CoV-2 infection in the general population
Sheila O’Brien, Canadian Blood Services
In this study, Canadian Blood Services aims to test approximately half a million samples from blood donors over a two-year period to provide data about COVID-19 infection rates in Canada. Samples will be monitored on a monthly basis using demographic and regional variables. Also, repeat donors will be tested multiple times to allow for longer-term tracking, and will possibly track how long immune responses to SARS-CoV-2 infection last.
Research summary Results Study website View study on
Canadian COVID-19 Prospective Cohort Study (CANCOV)
Angela Cheung and Margaret Herridge, University Health Network
The Canadian COVID-19 Prospective Cohort Study (CANCOV) aims to provide a comprehensive evaluation of early to one-year outcomes in 2,000 patients with COVID-19 infection and 500 family caregivers from the four hardest-hit provinces in Canada: Quebec, Ontario, Alberta, and British Columbia.
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Saskatchewan SARS-CoV-2 Seroprevalence Protocol (Phase I/Retrospective- lab analysis only)
Maureen Anderson, University of Saskatchewan
This study aims to understand what proportion of the population in Saskatchewan has immunity to SARS-CoV-2 by geographic area, age group and sex, in order to establish the cumulative population immunity. Researchers are also examining how long immunity lasts and helping to target vaccination campaigns.
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Manitoba COVID Seroprevalence Study (MCS Study)
Derek Stein, University of Manitoba
This study will take blood samples from Manitobans every two to three months to provide up-to-date estimates of COVID-19 prevalence. It will measure seroprevalence in the general population in Manitoba by sex, age, and regional health authority, determine risk factors for infection and improve estimates of case fatality ratio.
Research summary Results Study website View study on
Kami Kandola
Kami Kandola
Adj. Professor, Public Health & Preventive Medicine Program, University of Calgary & University of Alberta Clinical title and affiliated institution
Chief Public Health Officer, Government of Northwest Territories
Contact info
Kami_Kandola@gov.nt.ca
Key words
Public health, remote, northern and isolated, indigenous health
Research interests
Communicable diseases and outbreak response
Air quality and wildfires
Toxic drug supply
Age-stratified SARS-CoV-2 Serological Prevalence Estimation Using Anonymized Residual Sera Following Delta and Omicron Waves in the Northwest Territories (NWT)
Estimating age-stratified seroprevalence in the Northwest Territories
In the Northwest Territories (NWT) more than 10,000 SARS-CoV-2 infections were reported between March 2020 and March 2022 (the majority of cases were self-reported rapid antigen tests from late December 2021 to March 2022), and over 99,000 vaccine doses were provided to NWT residents by March 2022. When the public health emergency was lifted in April 2022, NWT changed its reporting requirements to include only severe COVID-19 outcomes. This meant the public health authority could no longer assess overall burden of COVID-19 on the NWT population other than through its territorial wastewater monitoring program. To address this, a cross-sectional sero-survey was designed to estimate the seroprevalence of SARS-CoV-2 among NWT residents, and inform future interventions.
This serological survey estimates the seroprevalence of antibodies to SARS-CoV-2 from vaccination and infection in the NWT population by age group and region. The objectives are to help ascertain the cumulative population immunity and estimate the fraction of asymptomatic, pre-symptomatic or subclinical infections in the population not identified by surveillance measures during previous waves of infection.
The sero-survey uses anonymized residual sera to describe the prevalence of SARS-CoV-2 antibodies resulting from infection and immunization. Residual sera is labelled with a unique identifier with all previous identifiers removed. The sero-survey provides a means to assess true population immunity in a validated and generalizable format, which helps with future modeling on potential health system impacts.
A total of four time points are being sampled to help solidify enough data for the NWT to understand the evolving risk that SARS-CoV-2 presents.
Age-stratified SARS-CoV-2 Serological Prevalence Estimation Using Anonymized Residual Sera Following Delta and Omicron Waves in the Northwest Territories (NWT)
Derek Stein
Derek Stein
Assistant Professor, University of Manitoba, Medical Microbiology and Infectious Diseases
Scientist, Cadham Provincial Laboratory
Contact info
Derek.Stein@gov.mb.ca
Key words
Serology
Seroprevalence
COVID-19
SARS-Cov-2
Research interests
SARS-CoV-2
Syphilis
STBBIs
Publications
Comparison of commercial assays and laboratory developed tests for detection of SARS-CoV-2, https://doi.org/10.1016/j.jviromet.2020.113970
Simulated sunlight decreases the viability of SARS-CoV-2 in mucus, https://doi.org/10.1371/journal.pone.0253068
Expansion of tissue-resident CD8+ T cells and CD4+ Th17 cells in the nasal mucosa following mRNA COVID-19 vaccination, bioRxiv
Dried blood spot specimens for SARS-CoV-2 antibody testing: A multi-site, multi-assay comparison, Research Square
Evaluation of commercial SARS-CoV-2 serological assays in Canadian public health laboratories, https://doi.org/10.1016/j.diagmicrobio.2021.115412
Practical guidance for clinical laboratories for SARS-CoV-2 serology testing, 10.14745/ccdr.v47i04a01
Manitoba COVID Seroprevalence Study (MCS Study)
Across Canada, many provincial governments and public health authorities have established seroprevalence studies to gather data on SARS-CoV-2 infections to better understand the extent of COVID-19 spread in their population and adapt public health measures accordingly.
In Manitoba, Cadham Provincial Laboratory (CPL) has initiated a surveillance study, called the Manitoba COVID Seroprevalence (MCS) study, to estimate the prevalence of COVID-19 within the province. The study is designed to sample the Manitoba population every two to three months in order to provide up-to-date estimates of COVID-19 prevalence.
This study is population based and includes people from all age groups, and follows World Health Organization (WHO) approved protocols for COVID-19 seroprevalence investigation. Our study objectives include:
- measuring the seroprevalence of SARS-CoV-2 antibodies in the general population in Manitoba by sex, age, and regional health authority;
- determining risk factors for infection by age, gender, and region;
- improving the estimates of case fatality ratio.
Our study is taking place over a two-year period, and we are analyzing more than 10,000 blood samples from people in all age categories (ages 1-9, 10-19, 20-39, 40-59, and 60+) from all of Manitoba’s six regional health authorities.
This prevalence study will allow public health officials to estimate the number of undiagnosed infections in Manitoba and determine the proportion of the population that is susceptible to COVID-19 disease. The study results will ultimately allow officials to implement public health policies in response to changing trends over time.
CITF-funded findings on pan-Canadian serosurveillance
About 60% of Manitobans had infection-acquired SARS-CoV-2 antibodies by winter 2022
A CITF-funded study, published in BMC Public Health, aimed to obtain a more accurate estimate of the true infection burden of SARS-CoV-2 in the province of Manitoba by accounting for all age groups, vaccination status, and waning antibody levels.
CITF-funded findings on pan-Canadian serosurveillance
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.
Maureen Anderson
Maureen Anderson, PhD
Assistant Professor, Department of Community Health and Epidemiology, College of Medicine, University of Saskatchewan
Technical Advisor, Public Health Surveillance, SK pandemic response
Contact info
Maureen.anderson@usask.ca
Key words
SARS-CoV-2; seroprevalence; duration of protection; vaccination; Delta; Saskatchewan
Research interests
Population and public health
Infectious disease epidemiology
Field epidemiology
Publications
Anderson M, Chhetri A, Halyk E, Lang A, McDonald R, Kryzanowski J, Minion J, Trecker M. An outbreak of COVID-19 in a fitness centre in Saskatchewan: Lessons for Prevention. Canadian Communicable Disease Report [accepted Sep 2021]
Trecker MA, Konrad S, Yalamanchili DT, Langhorst K, Anderson M. In-person learning low risk for COVID-19 acquisition: Findings from a population-based analysis of the 2020/21 school year in Saskatchewan. [submitted Oct 2021]
Saskatchewan SARS-CoV-2 Seroprevalence Protocol (Phase I/Retrospective- lab analysis only)
Our study team, which includes Maureen Anderson, Lesley Behl, Amanda Lang, Stephen Lee, Jessica Minion, and Cory Neudorf, is analyzing a total of 20,000 blood serum samples collected for screening purposes in Saskatchewan from May to December 2020 (prior to vaccine administration), and from October 2021 to at least June 2022 (following and coinciding with vaccine delivery). The study’s primary objective is to understand what proportion of the population in Saskatchewan has immunity to the virus by geographic area, age group and sex, in order to establish the cumulative population immunity.
The study’s secondary objectives include:
- examining how long protection lasts at a population level by analyzing antibody titre levels and length of time since vaccination,
- helping target vaccination to areas of the province with lower estimates of population immunity,
- comparing provincial population immunity before and after COVID-19 vaccination roll-out, and before and after variants of concern are identified in the population, and
- estimating the proportion of vaccine-induced immunity in the population versus infection-acquired immunity.
At the time when this study started, in the fall of 2021, not much information was available about how antibodies wane over time following vaccination. By collecting residual serum samples, conducting qualitative and quantitative testing for antibody levels, and then linking samples to patient COVID-19 immunization history, we will be able to assess seroprevalence rates and the impact of vaccines on antibody levels.
We will provide data from our study to the COVID-19 Immunity Task Force, Saskatchewan Health Authority, and the Government of Saskatchewan. Data collected will indirectly benefit participants through an increased understanding of COVID-19 in the province.
CITF-funded findings on pan-Canadian serosurveillance
CITF-funded findings on pan-Canadian serosurveillance
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.
Philip Awadalla
Philip Awadalla, PhD
Professor, Department of Molecular Genetics, Faculty of Medicine, University of Toronto
Professor, Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto
Adjunct Professor, CHUM, Department of Medicine, Faculty of Medicine, University of Montreal
Director, Computational Biology, Ontario Institute for Cancer Research
Senior Investigator, Ontario Institute for Cancer Research
National Scientific Director, Canadian Partnership for Tomorrow’s Health (CanPath)
Executive Scientific Director, Ontario Health Study
Principal Investigator and Director, Genome Canada Canadian Data Integration Centre
Key words
Canadian Partnership for Tomorrow’s Health (CanPath), SUPPORT-Canada, Ontario Health Study, Serology, Immunity, COVID-prevalence, Genomics
Research interests
– Genomics
– Early Cancer Detection
– Quantitative and population genetics
– Precision medicine
– Cancer diagnostic markers development
– Big data and Machine Intelligence
Publications
– CPHA Webinar – CanPath COVID-19 Questionnaire Results: A Preliminary Analysis
– Ouellette TW, Shaw J, Awadalla P. Using image-based haplotype alignments to map global adaptation of SARS-CoV-2. 2021. Biorxiv (and in review)
COVID-19 antibodies among high-risk populations in Canada
This pan-Canadian study tests 20,000 participants from high-risk populations for antibodies to SARS-CoV-2 (the virus that causes COVID-19), an indication of past infection. Our study focuses on individuals aged 30 and older, who may have been exposed to SARS-CoV-2, from populations that are traditionally not included in studies or that have the highest risk of exposure to COVID-19.
Participants include residents of long-term care and retirement homes; self-declared immigrants; and individuals living in underserved urban and rural communities with higher numbers of COVID-19 cases.
The project leverages access to the more than 330,000 volunteer Canadians enrolled with the Canadian Partnership for Tomorrow’s Health (CanPath), the largest population health study platform in the country.
This initiative is implemented in collaboration with CanPath’s regional cohorts: the BC Generations Project, Alberta’s Tomorrow Project, the Manitoba Tomorrow Project, the Ontario Health Study, CARTaGENE (Quebec), and the Atlantic Partnership for Tomorrow’s Health. The project includes a first round of dried blood spot collection and a questionnaire that identifies health and risk factor information, as well as COVID-19 testing and vaccination information.
A key strength of our study is that CanPath participants have already consented to linkage to administrative health databases, including public health testing results, which enables the capture of health services use and clinical outcomes to complement health and lifestyle information.
Our findings will help improve our understanding of the spread of COVID-19 among populations at higher risk of infection and allow us to plan and target public health approaches more effectively.
Results: SUrveying Prospective Population cOhorts for COVID19 pRevalence and ouTcomes in Canada (SUPPORT-Canada)
CITF-funded findings on vaccine safety and effectiveness
CITF-funded studies show the important role that vaccines have played in protecting Canadians and people worldwide from severe COVID-19. Here, we summarize results from the five presentations given during the breakout session “Vaccine safety and effectiveness” at the CITF Scientific Meeting in Vancouver, March 8-10, 2023.
Vaccine hesitancy among adults during Quebec’s COVID-19 vaccination campaign
Published in Frontiers in Public Health, the CARTaGENE research team, based at the Research Center at the Centre Hospitalier Universitaire Sainte-Justine and part of the CITF-funded CanPATH study, found that vaccination hesitancy among adults in Quebec was correlated with education levels, age and other socio-demographic determinants.
Early results from a national study confirm antibody levels are stronger after receiving two doses
Initial preliminary results from the Canadian Partnership for Tomorrow’s Health (CanPath) COVID-19 Antibody Study, based on close to 6,000 dried blood spot samples collected between February 8 and May 17, 2021, show a high degree of variability in the level of antibodies produced by a single dose of a COVID-19 vaccine. These findings highlight the importance of accelerating second doses as the Delta variant continues to spread, particularly with the vast majority of Canadians having received only a single vaccine dose.
Results: The Canadian COVID-19 Antibody and Health Survey (CCAHS)
CITF-funded findings on Post-COVID Conditions
It is now estimated that nearly 1 in 10 people who have a SARS-CoV-2 infection (hospitalized and non-hospitalized individuals) may develop Long COVID, which amounts to a global burden of over 16 million people.
Canada’s most representative study to date investigating how many Canadians have antibodies to SARS-CoV-2, the virus causing COVID-19, reveals a mere 2.6% of Canadians tested between November 2020 and April 2021 had developed antibodies resulting from a past infection. Another 1% of Canadians had antibodies due to vaccination, reflecting the fact that vaccination was not widely available during the survey period. This brings the total percentage of Canadians with some form of immunity before the third wave to 3.6%. These data come from Statistics Canada’s Canadian COVID-19 Antibody and Health Survey (CCAHS), done in partnership with Canada’s COVID-19 Immunity Task Force (CITF), the Public Health Agency of Canada, and Health Canada.
Surveying prospective population cohorts for COVID19 prevalence and outcomes in Canada (SUPPORT-Canada)
Our large number of participants, pan-Canadian reach, and population coverage allow us to capture how age, sex, socio-demographic factors, geography, genetics, and health history can impact immune responses to COVID-19.
With data from a survey that we implemented in 2020, we are able to identify participants who may have been exposed as well as infected. We can also identify how pre-existing conditions, captured through health information routinely collected over the past decade, impact COVID-19 disease severity. This project also includes a seroprevalence study of 3,000 participants at three time points, which enables us to capture immunity signatures both pre- and post-vaccination. Identifying diagnosed and symptomatic participants within the population enables rapid surveillance that supports Canada’s public health agencies at the community and individual levels — and helps shed light on the unequal distribution of COVID-19 across the country.
This COVID-19-specific information also allows us to provide the scientific community with timely data to support research on surveillance, prevention, and risk factors.
Angela Cheung
Co-Lead PI for CANCOV (Canadian COVID-19 Longitudinal Cohort Study), University Health Network
Staff General Internist, Senior Scientist, University Health Network
Contact info
angela.cheung@uhn.ca
Key words
COVID-19
Acute respiratory distress syndrome
Severe acute respiratory syndrome
ICU
Hospitalized
Non-hospitalized
Cohort
Research interests
Integrative medicine
Genetic and clinical risk factors
Sarcopenia, osteoporosis, frailty
Sex and Gender, and Racial differences
Functional outcomes, quality of life, and health services research
Cost-effectiveness analyses, medical decision making
Publications
https://pubmed.ncbi.nlm.nih.gov/?term=Cheung+AM%5BAU%5D+NOT+Cheung+AMS%5BAU%5D+NOT+Cheung+AMC%5BAU%5D+AND+%28Toronto%5BAD%5D+OR+UHN%5BAD%5D%29&sort=date
https://www.scopus.com/authid/detail.uri?authorId=7401806456
https://orcid.org/0000-0001-8332-0744
Margaret Herridge
Professor of Medicine, University of Toronto
Physician, Toronto General Hospital
Senior Scientist, Toronto General Hospital Research Institute
Co-Lead PI for CANCOV (Canadian COVID-19 Longitudinal Cohort Study), University Health Network
Director of Critical Care Research, Interdepartmental Division of Critical Care Medicine, University of Toronto
Faculty, Institute of Health Policy, Management and Evaluation, University of Toronto
Contact info
margaret.herridge@uhn.ca
Key words
COVID-19
Acute respiratory distress syndrome (ARDS)
Severe acute respiratory syndrome (SARS)
ICU
Hospitalized
Critical Care
Family caregivers
prolonged mechanical ventilation
Research interests
Long-term outcomes after ARDS
SARS
prolonged mechanical ventilation
COVID-19
RECOVER Program
Patient- and family-centred follow-up care after critical illness;
CANCOV Program
Publications
https://pubmed.ncbi.nlm.nih.gov/?term=Herridge+M%5BAU%5D+NOT+3475205%5BPMID%5D&sort=date
https://www.scopus.com/authid/detail.uri?authorId=6701511275
https://orcid.org/0000-0002-2903-1631
Canadian COVID-19 Prospective Cohort Study (CANCOV)
Co-led by Dr. Angela M. Cheung and Dr. Margaret S. Herridge, CANCOV is a consortium of interdisciplinary investigators and clinicians leading multiple COVID-19 studies across Canada. Our research ranges from genomics and epigenomics to antibody testing and immune analyses.
This study involves the recruitment of 2,000 patients (1,000 non-hospitalized and 1,000 hospitalized) and 500 family caregivers from the four hardest-hit provinces in Canada: Quebec, Ontario, Alberta, and British Columbia. Our research includes three COVID-19 population cohorts: non-hospitalized patients, non-ICU patients, and ICU patients.
This research program intends to:
- Characterize the myriad health consequences of COVID-19, including short- and long-term outcomes and those of the family caregivers;
- Determine the clinical risk factors, timing, and pace of recovery across the spectrum of COVID-19 disease;
- Provide detailed clinical descriptions for genetic, basic science, translational, and multi-omics research inquiry; and
- Facilitate the creation of prediction models and tools, using machine learning and artificial intelligence, as well as secondary clinical studies.
CANCOV will raise the standard of care for patients with COVID-19 and shorten the time to translate knowledge into practice. Insights from this large-scale project will enable Canada to improve COVID-19 clinical care and help service providers and policymakers make better decisions.
Canadian COVID-19 Prospective Cohort Study (CANCOV)
HostSeq: A Canadian consortium collecting genetic data to identify factors associated with COVID-19
The HostSeq platform, established in April 2020, is a national collaboration of population-based studies investigating the genetic risk factors behind SARS-CoV-2 infection and health outcomes associated with it.
Marc Germain
Marc Germain, PhD.
Vice President, Medical Affairs and Innovation, Héma-Québec
Keywords
Transfusion, epidemiology, infectious diseases
Research areas
Transfusion epidemiology, blood-borne diseases
Publications
Approx 60″
Seroprevalence study and cross-validation of high-throughput serological tests conducted by the COVID-19 Immunity Task Force (Héma-Québec)
Understanding the level of SARS-CoV-2 infection in the general public is a key factor for public health management of COVID-19 disease. Quebecers who volunteer to donate blood are representative of the population at large; they range in age from 18 to 69 and live in every region of the province. Studying this group provides an effective way to gather data about SARS-CoV-2 infection and the progression of immunity in the population.
Our study goal is to estimate how many people have contracted the SARS-CoV-2 virus in Quebec or have antibodies to the virus due to vaccination. We are doing this by determining the prevalence of antibodies in a sample number of blood donors. Our study started in May 2020 after the first wave of the COVID-19 pandemic and data continues to be collected and analyzed at various intervals.
Héma-Québec is well-positioned for such a study, as it has both laboratories and in-house expertise to test samples from regular blood donations.
This study is being funded by Quebec’s Institut national de santé publique (INSPQ). The COVID-19 Immunity Task Force is a partner, supporting the cross-validation of results, meaning an evaluation of results based on five commercially available antibody detection tests in order to standardize interpretation of results.
Results: Seroprevalence study and cross-validation of high-throughput serological tests conducted by the COVID-19 Immunity Task Force (Héma-Québec)
CITF-funded findings on methodologic approaches to improve seroprevalence estimates
Assessing seroprevalence is the main methodology used in Canada and around the world to determine the extent and trends in SARS-CoV-2 immunity, whether from infection, vaccination, or both.
Characteristics of Quebec plasma donors used to study COVID-19 immunity
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.
A recent serosurvey conducted by Héma-Québec estimates that 27.4% of adults in the province developed infection-acquired antibodies to SARS-CoV-2 between January and mid-March 2022, during the first Omicron wave.
Young adults remain the primary vector of SARS-CoV-2 transmission: Latest data from Héma-Québec
The latest serosurvey conducted by Héma-Québec estimates that 45.3% of adults in Quebec developed infection-acquired antibodies to SARS-CoV-2 between December 2021 and June 2022, up from 27.3% in mid-March 2022.
A novel method for detecting SARS-CoV-2 seroprevalence
In a preprint, not yet peer-reviewed, CITF-funded researchers developed a novel approach to detect SARS-CoV-2 anti-nucleocapsid antibodies. The ratio-based approach had a 95.2% sensitivity among both previously vaccinated and previously infected donors compared with 63.3% for the conventional approach.
In a study partially funded by the CITF and published in Cell Reports, Drs. Andrés Finzi (Université de Montréal) and Renée Bazin (Héma-Québec) showed that a third vaccine dose elicited strong antibody responses regardless of the interval between the first and second doses.
Study of blood donors shows many asymptomatic infections during the first COVID-19 wave in Quebec
A study led by Héma-Québec, the provincial blood collection agency, supported by the CITF and featuring CITF-funded researcher, Dr. Andrés Finzi, showed that 2.23% of blood donors were seropositive for SARS-CoV-2 between May 25 and July 9, 2020: about four times higher than the number of PCR-confirmed COVID-19 cases during the same period.
Researchers from Université de Montréal and Héma Québec, led by Dr. Andrés Finzi and Dr. Renée Bazin, and working with collaborators across Canada, are reporting that antibodies against SARS-CoV-2 Spike correlate with COVID-19 severity.
A novel high-throughput method to screen convalescent plasma
Dr. Andrés Finzi from the Université de Montréal and Dr. Renée Bazin from Héma-Québec and their teams recently describe a novel high-throughput method to track levels of antibodies made against SARS-CoV-2 spike protein in the plasma of donors that recovered from COVID-19 in a recent issue of Transfusion.
The power of IgM in the immune response against SARS-CoV-2
Dr. Andrés Finzi, from the Université de Montréal, Dr. Renée Bazin from Héma-Québec, along with collaborators from Western University, are highlighting the importance of antibodies made early on in the infection in SARS-CoV-2 neutralization.
May 26, 2021
Recent blood donor data suggest that Canadians still remain vulnerable to SARS-CoV-2 infection
Blood donation organizations to provide important assessment of how long immunity lasts NEWS RELEASE MONTREAL, May 27, 2021 — Results from the latest Canadian Blood Services and Héma-Québec studies, which together cover all 10 provinces, confirm that from coast-to-coast, Canada’s overall levels of seroprevalence due to SARS-CoV-2 infection remained very low earlier […]
The COVID-19 Immunity Task Force welcomes the results of the blood donor seroprevalence study led by Héma-Québec and will be working with that organization to validate these results through the use of another antibody test. We look forward to reporting on these results in the coming weeks together with Héma-Québec. The Héma-Québec study results suggest […]
Ron Gravel
Statistics Canada
Director, Centre of Population Health Data
Key words
Health, statistics, data, population health, population surveys
Research interests
Health Statistics
Population Health Framework
mental health
population health outcomes
population health determinants
survey methods
Publications
Orpana HM, Lemyre L, Gravel R. Income and psychological distress: the role of the social environment. Health Rep. 2009 Mar;20(1):21-8. https://www150.statcan.gc.ca/n1/en/pub/82-003-x/2009001/article/10772-eng.pdf?st=rJRf3CkN
The Human Face of Mental Health and Mental Illness in Canada. Lead Senior Analyst for Statistics Canada, Public Health Agency of Canada, Cat. No. HP5-19/2006E. 2006. https://www.phac-aspc.gc.ca/publicat/human-humain06/pdf/human_face_e.pdf
Barr RG, Pantel MS, Young SN, Wright JH, Hendricks LA, Gravel R. The response of crying newborns to sucrose: is it a “sweetness” effect? Physiol Behav. 1999 May;66(3):409-17. doi: 10.1016/s0031-9384(98)00294-7.
Pepler C, Edgar L, Gilmore N, Ladd H, Morrison K, Sampalis J, Seguin E, Gravel R. The effect of focused coping skills programs on perceived control and well-being in HIV + persons. 1999. Final Report submitted to the National Health Research and Development Program, Health Canada: Project #6605-4531-AIDS, Ottawa, Canada.
Gravel RG. The Canadian Community Health Survey: Mental Health Survey Results. Statistics Canada Daily Release, September 2003, Ottawa, Ontario.
The Canadian COVID-19 Antibody and Health Survey (CCAHS)
Through integration with health and social administrative data, this project also provides a platform to explore emerging public health issues, including the impact of COVID-19 on health and social wellbeing.
The study involves both an online questionnaire and a small blood sample using a dried blood spot method. The questionnaire asks sociodemographic questions and gathers information on COVID-19 exposure, experiences, symptoms, and vaccination uptake. Participants will be able to learn the results from their blood sample, along with information on what is currently known about antibody testing.
Test kits and surveys are sent to 48,000 Canadians at their homes in both rural and urban settings in all 10 provinces and three territories. Interviewers will follow-up by telephone with non-responders to improve response rates.
(Participants do not directly volunteer; they have been chosen based on a formula determined to obtain the most representative population sample for the study’s goals.)
This study will provide important information on how much transmission there has been, in which parts of the country, and among which populations. Our findings will help to further inform the public health response to COVID-19 in all provinces and territories across the country.
Canadian COVID-19 Antibody and Health Survey (CCAHS) second cycle
This second cycle of the Canadian COVID-19 Antibody and Health Survey (CCAHS) aims to better understand the impacts of the pandemic on the health and well-being of Canadians, including the prevalence of chronic symptoms and conditions and the challenges that Canadians may have faced in accessing healthcare.
A partnership between Statistics Canada, the Public Health Agency of Canada (PHAC) and the COVID-19 Immunity Task Force (CITF), the study will estimate the prevalence of post COVID-19 condition (commonly known as long COVID) in Canada, and will provide information on the risk factors, symptoms, and impacts of this condition on daily functioning.
The CITF is funding the portions of the study focussing on understanding the prevalence of SARS-CoV-2 antibodies in the Canadian population. This study aims to establish a statistically representative understanding of the number of Canadian adults with COVID-19 antibodies, whether due to COVID-19 vaccination and/or a previous SARS-CoV-2 infection. The study will also provide a picture of the number of Canadians who were infected at the time of the survey through saliva testing in two-thirds of participants.
From April to June 2022, a total of 100,000 individuals (18 and over) across 10 provinces were asked to take part in the survey. The first group (33,000 people) were asked to collect their own dried blood spot (DBS) sample to test for antibodies. The second and third groups (67,000 people total) are collecting both DBS for antibody testing and saliva specimens for Polymerase Chain Reaction (PCR) testing. Participants send their samples to Statistics Canada, which then sends these to various labs for analysis. Participants get a report as to whether antibodies were found in their blood sample and, for those who provide a saliva sample, whether the test shows they had an active infection at the time of the sample. Preliminary results from the survey will be available in the fall of 2022, with final results expected in early 2023.
Deborah Money
Professor, Department of Obstetrics & Gynaecology, Medicine, & SPPH, University of British Columbia
Clinician Scientist, Women’s Health Research Institute, BC Women’s Hospital
Key words
Reproductive Infectious Diseases
HIV
Maternal Microbiome
HPV
COVID-19 in Pregnancy
Research interests
My early research interests focused on viral infections in pregnancy, including HIV, Hepatitis C, and Herpes simplex. I led a Canada-wide study of HPV, the HPV vaccine and cervical cancer in women living with HIV. In the last ~10 years, I have also been leading a program of women’s focused personalized medicine in the area of understanding the vaginal microbiome in health and disease, studying the impact of the maternal microbiome on the infant gut microbiome. Most recently, my research team pivoted to study COVID-19 in pregnancy, through CANCOVID-Preg and a seroprevalence study utilizing antenatal sera.
Canadian Population Serological Survey Utilizing Antenatal Serum Samples
Pregnant women undergo routine blood screening as part of prenatal care, and they are representative of generally healthy adults aged 18 to 45 across socioeconomic and cultural backgrounds. Our study, titled the Canadian Population Serological Survey Utilizing Antenatal Serum Samples, analyzes blood samples from expectant women across the country — to help determine the prevalence and spread of SARS-CoV-2 in Canada.
Leveraging these existing blood samples, our research team is striving to answer key questions about the serological prevalence of SARS-CoV-2 antibodies.
Phase 1 of this study has seen our team work towards completing an immediate cross-sectional survey of seroprevalence across the provinces and territories. Using serological tests, the aim was to gather a representative group of the Canadian population to inform the public health response to the COVID-19 pandemic. Following that, we have been assessing the evolution of SARS-CoV-2 prevalence using antenatal samples periodically.
Our study aims to provide necessary insights on the transmission dynamics of COVID-19 in this representative population. Findings can help us track the spread and impact of the virus in the Canadian population, as well as provide insights into the COVID-19 immune response.
Sheila O'Brien
Dr. Sheila O’Brien
Adjunct Professor, School of Epidemiology & Public Health, University of Ottawa
Associate Director, Epidemiology and Surveillance, Canadian Blood Services
Contact info
sheila.obrien@blood.ca
Key words
Seroprevalence
Epidemiology
Surveillance
Transfusion medicine
Blood donor health
Research interests
Blood-borne pathogens
Mathematical risk modelling
Blood donor health
Publications
Saeed S, Drews SJ, Pambrun C, Yi QL, Osmond L, O’Brien SF. SARS-CoV-2 seroprevalence among blood donors after the first COVID-19 wave in Canada. Transfusion 2021:61:862-872
Canadian Blood Services: Testing for SARS-CoV-2 infection in the general population
Canadians who donate blood are presumed to be generally healthy. CBS has long-established procedures to ensure blood supply safety, and for the 13,000 to 20,000 blood donations we collect across Canada every week (excluding Quebec and the Territories), our standard practice is to keep a plasma sample of each for one week in case extra testing is required. In spring 2020, we quickly implemented a process to store the 80 per cent of plasma samples not needed for further testing and test them for SARS-CoV-2 antibodies.
The study goals, approved by our Research Ethics Board, include analyzing approximately half a million samples over a two-year period, which we will monitor on a monthly basis using demographic and regional variables. We are testing some donors multiple times to allow for longer-term tracking, and will possibly track how long immune responses to SARS-CoV-2 infection last.
We have also incorporated a new testing method in the study that differentiates between infection-acquired immunity and vaccine-acquired immunity. Our study began in May 2020, and as of January 2021 we have tested about 160,000 samples. In wave 1 (May to July 2020) less than one per cent of blood donors had coronavirus antibodies. By January 2021 there were about two per cent who had antibodies. These low numbers indicate that vaccines will be essential to achieving immunity in the general population.
Results: Canadian Blood Services: Testing for SARS-CoV-2 infection in the general population
The latest CITF-funded report from Canadian Blood Services suggests that seroprevalence due to infection was 82.68% in December 2023, in line with the 82.97% found in November 2023. Consistent with previous reports, the percentage of younger donors (ages 17-24) who had infection-acquired seroprevalence was the highest of all donor age groups.
The latest CITF-funded report from Canadian Blood Services suggests that seroprevalence due to infection was 83% in November 2023, up slightly from 81.6% in October 2023. This increase was not statistically significant.
Enhanced immune responses were observed with longer intervals between COVID-19 vaccine doses
A CITF-funded study, published in Cureus, examined the impact of different dosing intervals between the first two COVID-19 mRNA vaccines. Intervals longer than 38 days, compared to a short interval of less than 30 days, resulted in higher levels of SARS-CoV-2 anti-spike antibodies.
Seroprevalence due to infection stable around 80% in Canadian blood donors in October
The latest CITF-funded report from Canadian Blood Services suggests that seroprevalence due to infection is now stable among Canadian blood donors at approximately 80%.
Seroprevalence due to infection stable at 80% at start of the back-to-school season
The latest CITF-funded report from Canadian Blood Services suggested that seroprevalence due to infection was 80.1% among Canadian blood donors at the end of September 2023. This increased slightly from the 79.0% seroprevalence observed in August 2023.
Seroprevalence due to infection continued to be stable near the 80% mark in August
The latest CITF-funded report from Canadian Blood Services suggested that seroprevalence due to infection was 79.03% among Canadian blood donors in August 2023.
Seroprevalence due to infection stable at 80% in July
The latest CITF-funded report from Canadian Blood Services suggests that seroprevalence due to infection was stable at 80% among Canadian blood donors by the end of July.
Seroprevalence due to infection among Canadian blood donors reached the 80% mark in June
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.
CITF-funded findings on pan-Canadian serosurveillance
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.
Seroprevalence due to infection was 79.6% in May, similar to April
The latest CITF-funded seroprevalence report from Canadian Blood Services shows that approximately 79.6% of adult blood donors had infection-acquired seroprevalence in May, which is similar to April (79.4%).
Infection-acquired seroprevalence exceeded 70% by the end of November: Canadian Blood Services.
Among Canadian Blood donors, the infection-acquired seroprevalence continued to rise in the month of November 2022, to 71%, up from 67.4%, at the end of October.
Striking differences in SARS-CoV-2 seroprevalence across Canada by social determinants of health
In a paper published in Microbiology Spectrum, CITF-funded researchers, including at Canadian Blood Services, showed that infection-acquired immunity to SARS-CoV-2 varied, in 2021, by age, region, racial group, the neighbourhoods in which people lived and whether they were materially or socially deprived (had fewer contacts). Interestingly, these factors were not consistent throughout all provinces and regions.
Infection-acquired seroprevalence continued to increase in September: Canadian Blood Services.
Consistent with the continued prevalence of the Omicron variants (predominantly BA.4, BA.5 and BA.5 subvariants), infection-acquired seropositivity continues to increase among blood donors, up to 65.41% by the end of September, from 60% in the last week of August. These data come from Canadian Blood Services.
Neutralization capacity against SARS-COV-2 in blood donors
This study, published in Microbiology Spectrum and carried out by CITF-funded researchers Drs. Steven Drews and Sheila O’Brien of Canadian Blood Services, characterized the neutralization capacity and the breadth of protection against SARS-CoV-2 and its variants of concern (Alpha, Beta, Gamma, and Delta).
Global seroprevalence of SARS-CoV-2: Updated data from SeroTracker
A study carried out by SeroTracker (a CITF-funded project), in partnership with the World Health Organization, found global SARS-CoV-2 seroprevalence (due to infection or vaccination or both) was 45.2% by end of June 2021.
Using multiple assays and models to help decipher true Canadian seropositivity
Using various serological assays in parallel on the same set of samples can produce inconsistent results. A solution is to use composite reference standards and latent class analysis to help decipher true seropositivity.
Vaccine hesitancy among adults during Quebec’s COVID-19 vaccination campaign
Published in Frontiers in Public Health, the CARTaGENE research team, based at the Research Center at the Centre Hospitalier Universitaire Sainte-Justine and part of the CITF-funded CanPATH study, found that vaccination hesitancy among adults in Quebec was correlated with education levels, age and other socio-demographic determinants.
Antibody trends in the first 11 months of 2021: Canadian Blood Services
In a paper published in Microbiology Spectrum, researchers with Canadian Blood Services (CBS) point to the changing patterns of infection-acquired and vaccine-induced seroprevalence, observed between January and November 2021.
Immune responses to mRNA COVID-19 vaccine in immune-deficient patients
A paper now published in JCI Insight by CITF-funded researchers Drs. Anne-Claude Gingras, Tania Watts, and Vinod Chandran of the University of Toronto provides evidence of the need for a third dose of mRNA vaccine in patients with immune-mediated inflammatory diseases (IMID).
HostSeq: A Canadian consortium collecting genetic data to identify factors associated with COVID-19
The HostSeq platform, established in April 2020, is a national collaboration of population-based studies investigating the genetic risk factors behind SARS-CoV-2 infection and health outcomes associated with it.
Consistent with the ongoing transmission of the Omicron variant, infection-acquired seropositivity increased in the blood donor community gradually throughout May, from 36.71% at the end of April to 48.96% at the end of May, according to data from Canadian Blood Services.
Unvaccinated paramedics at greater risk of COVID-19 infection
As part of the COVID-19 Occupational Risks, Seroprevalence and Immunity among Paramedics (CORSIP) study, CIFT-funded researchers Drs. Brian Grunau and David Goldfarb (University of British Columbia) did not find that, during the pre-Omicron waves, paramedics were at higher risk of catching SARS-CoV-2 than a control group of blood donors.
Evidence suggests SARS-CoV-2 transmissions in school less than in community at large
A preprint, not yet peer-reviewed, from a CITF-funded study, suggests that the chances of adults getting infected with SARS-CoV-2 was lower in the school setting than it was in the community, even during the first Omicron wave.
Anti-SARS-CoV-2 assay proves nearly 90% effective in detecting COVID-19 infection
A CITF-funded study, led by Drs. Brian Grunau and David Goldfarb and Pascal Lavoie (University of British Columbia), and Sheila O’Brien and Steven Drews of Canadian Blood Services, and published in Open Forum Infectious Diseases, tested the sensitivity of the Roche anti-SARS-CoV-2 nucleocapsid assay.
Seroprevalence increases again in June but stabilizes throughout month: Canadian Blood Services
With the continued transmission of the Omicron variant in Canada, infection-acquired seroprevalence increased again within the blood donor community, from 46.3% at the end of May to 50.7% by the end of June.
Young adults remain the primary vector of SARS-CoV-2 transmission: Latest data from Héma-Québec
The latest serosurvey conducted by Héma-Québec estimates that 45.3% of adults in Quebec developed infection-acquired antibodies to SARS-CoV-2 between December 2021 and June 2022, up from 27.3% in mid-March 2022.
A novel method for detecting SARS-CoV-2 seroprevalence
In a preprint, not yet peer-reviewed, CITF-funded researchers developed a novel approach to detect SARS-CoV-2 anti-nucleocapsid antibodies. The ratio-based approach had a 95.2% sensitivity among both previously vaccinated and previously infected donors compared with 63.3% for the conventional approach.
Infection-acquired seroprevalence increased in July: Canadian Blood Services
Due to continued transmission of the newer Omicron variants (BA.4 and BA.5) in Canada, infection-acquired seropositivity increased within the blood donor community, from 50.7% at the end of June to 54% by the end of July, with a modest week-to-week change throughout July.
Third dose improves immunity to SARS-CoV-2 in immunocompromised patients
In a letter published in RMD Open, CITF-funded researchers found that SARS-CoV-2 antibody levels and T cell responses increased following a third dose of vaccine in immunocompromised patients. Drs. Vinod Chandran, Anne-Claude Gingras, and Tania Watts (University of Toronto) showed that 92% of COVID-naïve patients with immune-mediated inflammatory disease (IMID) showed anti-spike and anti-RBD antibody levels that were greater than convalescent individuals (those recovering from COVID-19 infection).
A systematic review and meta-analysis of seroprevalence of SARS-CoV-2 in Africa
In a systemic review published in BMJ Global Health, Dr. Rahul Arora (University of Calgary) and the CITF-funded SeroTracker team estimates that seroprevalence in Africa (due to infection or vaccination) was 65.1% in July-September 2021.
The promise held by quantitative immunoassays to identify antibody-rich donor plasma
A new study, published in Microbiology Spectrum from the CITF-funded Canadian Blood Services (CBS) team led by Drs. Sheila O’Brien and Steven Drews, characterizes the ability of a new immunoassay to specify the concentration of neutralizing antibodies against SARS-CoV-2 in blood plasma.
Infection-acquired seroprevalence increased again in August: Canadian Blood Services
Omicron and its subvariants (BA.4 and BA.5) continued to spread in Canada in August. By the last week of August, 60% of blood donors had infection-acquired seropositivity, up from 56.5% at the end of July.
Identifying who participated in a seroprevalence study is a crucial metric
In a study published in the International Journal of Epidemiology, the CITF-funded SeroTracker team, including Dr. Rahul Arora (University of Calgary), contributed to showing that only 70% of individuals invited to participate in seroprevalence studies actually enrolled.
Blood circulating protein differences among individuals with acute COVD-19
In a publication in Clinical Proteomics led by Drs. Brent Richards and Guillaume Butler-Laporte (McGill University), CITF funded researcher Dr. Daniel Kaufmann (Université de Montréal) and Dr. Vincent Mooser (McGill University, former director of the Biobanque québécoise de la COVID-19 (BQC19)) determined that severe COVID-19 is associated with significant changes in 69 immune-related proteins.
A report published in the Annals of the New York Academy of Sciences, prepared with the participation of the CITF-funded Serotracker team, presents the outcomes of the April 2022 Keystone symposium on the successes and challenges of the COVID-19 pandemic. Rahul Arora (University of Calgary) participated as a representative of the CITF-funded SeroTracker initiative.
Systematic review of the serology assays used in COVID-19 seroprevalence surveys
A systematic review carried out by the CITF-funded SeroTracker team, released in preprint, and not yet peer reviewed, reported that third-party or independent evaluations from manufacturers found that the manufacturers appear to overstate the sensitivity and specificity of their serological assays targeting SARS-CoV-2.
Understanding community perceptions related to vaccine acceptance
A preprint, not yet peer-reviewed, from a CITF-funded study led by Dr. Sonia Anand (McMaster University) focused on the South Asian community to demonstrate that understanding factors such as community dynamics, language, and cultural context can help build vaccine confidence and acceptance among diverse population groups.
Infection-induced seroprevalence among blood donors rises during the Omicron wave
According to Canadian Blood Services data published in Viruses, infection-related seroprevalence increased with the emergence of the Omicron SARS-CoV-2 variant from September 2021 to June 2022.
The gap between the rates of COVID-19 infection and vaccination among racialized and non-racialized Canadians continues to exist, as does the gap between Canadians from lower- and higher-income neighbourhoods. The CITF-funded Canadian Blood Services Serosurveillance Study has released its latest report for the month of May 2021. While the latest data show that the […]
Latest Canadian Blood Services data reflect uptick in infections prior to Omicron surge
Remarkably, nearly all Canadian Blood Services blood donors sampled in November tested positive for antibodies against the SARS-CoV-2 spike protein. While this was mainly due to vaccination with at least one vaccine dose, seroprevalence from a prior infection with COVID-19 stood at 5.1%, higher than what was seen in previous months. In a subset […]
Canadian Blood Services December report: The advance of Omicron
The latest report from Canadian Blood Services, covering the early days of the Omicron wave, shows that, notwithstanding the nearly universal presence of anti-SARS-CoV-2 antibodies among blood donors, the number of donors who had antibodies due to prior infection rose. Key findings: The proportion of donors with evidence of a prior infection was 6.4% […]
Infection-acquired seropositivity increased throughout February 2022, averaging out to 23.7% for the month - double January’s rate of 12.1% - according to data from Canadian Blood Services.
Growth in infection-acquired immunity slows in early March
The latest data from Canadian Blood Services show the rapid increase in infection-induced immunity began slowing by mid-March. The data show infection-acquired seropositivity increased moderately between the end of February and mid-March, up to 27.5% from 25.3%.
A recent serosurvey conducted by Héma-Québec estimates that 27.4% of adults in the province developed infection-acquired antibodies to SARS-CoV-2 between January and mid-March 2022, during the first Omicron wave.
30% of Canadian Blood Services donors infected with SARS-CoV-2 by end of March 2022
Consistent with the ongoing transmission of the Omicron variant, infection-acquired seropositivity increased in the blood donor community gradually throughout March, from 27% to 30%.
Over half of Canadian blood donors aged 17 to 24 were infected with SARS-CoV-2 by mid-April
Blood donors between 17 and 24 years old have persistently experienced the highest seropositivity rate from infection. Mid-April data from the Canadian Blood Services show that a majority (52%) in this age group had evidence of infection-acquired antibodies (antibodies targeting the nucleocapsid protein).
Nearly 40% of Canadian adults have had an Omicron infection: Canadian Blood Services
Consistent with the ongoing transmission of the Omicron variant, infection-acquired seropositivity increased among blood donor throughout April, from 33% at the beginning of the month to 40% by the end.
Consistent with the ongoing transmission of the Omicron variant, infection-acquired seropositivity increased in the blood donor community gradually through the beginning of May, from 40% at the end of April to 46% by mid-May, according to the latest data from Canadian Blood Services.
35% more Canadian blood donors had infection-acquired antibodies by mid-February 2022
In its latest report, Canadian Blood Services revealed the toll of Omicron’s spread through mid-February 2022. Not only did 22.7% of all blood donors experience a prior SARS-CoV-2 infection, but this rate represented a 35% jump during the 22-day sampling period (January 24 – February 15).
Canadian Blood Services data reveal evidence of antibody wane among adult population
The latest Canadian Blood Services (CBS) report, from October 2021, indicates that 98% of blood donors sampled had antibodies to SARS-CoV-2. This number is largely driven by immunization with at least one vaccine dose, as infection-acquired seroprevalence stayed low, at 4.3%. Results also reveal a downward trend in the mean levels of antibodies across […]
May 26, 2021
The continued persistence of SARS-CoV-2 infections in predominantly unvaccinated individuals has meant a continued need for therapeutics to treat those hospitalized with COVID-19.
96% of Canadian blood donors have evidence of SARS-CoV-2 antibodies, primarily due to vaccination, a rate that has increased from 91% in June and 95% in July. This according to Canadian Blood Services’ 13th seroprevalence report, covering data from August 2021. Nonetheless, targeted efforts to alleviate infection burden and promote vaccine uptake are still […]
Newest Canadian Blood Services data mirrors widescale vaccine roll-out in Canada
The latest results from the Canadian Blood Services’ monthly serosurvey indicate that 95% of blood donors sampled in July 2021 had antibodies against SARS-CoV-2, acquired predominantly through vaccination. Not only did vaccine-induced seroprevalence increase among all sociodemographic groups and across all geographic regions, but infection-acquired seroprevalence dropped compared to June 2021. Donors identifying as […]
The month of June saw many Canadians rolling up their sleeves for a COVID-19 vaccine. The latest results from the Canadian Blood Services’ serosurvey reflect this, with vaccine-induced seroprevalence soaring to 86% across Canada (excluding the Territories and Quebec), up from 60% the month prior. Most importantly, the gap in vaccine coverage among socioeconomic […]
‘Made-in-Canada’ assays perform well to measure seroprevalence
A recent preprint, not yet peer reviewed, by CITF Testing Working Group members Dr. Anne-Claude Gingras from University of Toronto, and Dr. Steven Drews from Canadian Blood Services, compared multiple assays and concluded ‘Made-in-Canada’ ones performed well.
Recent blood donor data suggest that Canadians still remain vulnerable to SARS-CoV-2 infection
Blood donation organizations to provide important assessment of how long immunity lasts NEWS RELEASE MONTREAL, May 27, 2021 — Results from the latest Canadian Blood Services and Héma-Québec studies, which together cover all 10 provinces, confirm that from coast-to-coast, Canada’s overall levels of seroprevalence due to SARS-CoV-2 infection remained very low earlier […]
Latest Canadian findings point to widening inequalities in the fight against COVID-19
Serosurveillance survey shows SARS-CoV-2 infections growing much faster in poorer neighbourhoods and amongst racialized populations Results from the latest Canadian Blood Services/COVID-19 Immunity Task Force (CITF) collaborative nine-province seroprevalence study confirm that the pandemic is increasingly affecting poorer neighbourhoods and racialized populations. The inequalities in risk in getting COVID-19 were identified early in the pandemic […]
Canadian seroprevalence estimates from Canadian Blood Services, May 2020 to January 2021
View a table of Canadian seroprevalence estimates from Canadian Blood Services for May 2020 to January 2021. Links to full reports available as well.
Results from CBS’s initial survey, conducted between May 9th and July 21st, 2020 showed that 552 of the 74,642 donors tested had detectable antibodies, which gave an adjusted seroprevalence of 7.7 per 1000 donors.
Latest findings reveal few Canadian adults have antibodies to SARS-Cov-2
Canadian Blood Services and the CITF’s collaborative nine-province SARS-CoV-2 seroprevalence study for October thru November suggests that 1.5 per cent of healthy Canadians had been exposed to SARS-CoV-2. The highest levels were recorded in Western Canada but mass national vaccination remains only route to achieving herd immunity.
Other
SeroTracker
Rahul Arora, and TingTing Yan, University of Calgary
SeroTracker is a dashboard with data from SARS-CoV-2 serosurveillance projects from around the world. A Canada-only dashboard is also available. Many countries have invested in serosurveys to understand the true extent of the pandemic, identify groups at risk, monitor vaccine-induced immunity, and chart an exit strategy from the pandemic.
Immunity Passports for COVID-19: Scientific, Ethical, Policy and Design Implications
Kumanan Wilson, Bruyère Research Institute
Our study is evaluating the potential use of an immunity passport in Canada. We are examining the current international use and studying the specific implications for Canada. We will provide guidance on the potential design of an effective digital tool to manage immunity tracking, as the dynamic nature of the science is best suited to digital certification solutions.
Research summary Results Study website View study on
Biobanque québécoise de la COVID-19 (BQC19)
Vincent Mooser, McGill University
BQC19 is recruiting close to 5,000 individuals (children and adults) and collecting blood samples and clinical data to ensure that scientists have access to the biological materials and data necessary for their COVID-19 research. The biobank uses a network of universities and hospitals in Quebec and is part of larger biobank network in Canada and around the world.
Research summary Results Study website View study on
Tingting Yan
MD/MSc candidate, University of Toronto
Key words
Systematic review
Health policy
Global health
Public health
Health innovation
Research interests
Health policy
Global health
Public health
Health innovation
Data-driven and rapid evidence synthesis
Publications
Canada’s Testing and Screening Expert Advisory Panel [including Yan T]. Priority strategies to optimize testing and screening for primary and secondary schools [Internet]. Government of Canada; 2021 Mar. Available from: Government of Canada website.
Canada’s Testing and Screening Expert Advisory Panel [including Yan T]. Priority strategies to optimize testing and screening in long-term care homes [Internet]. Government of Canada; 2021 Feb. Available from: Government of Canada website.
Barlow KM, Iyer K, Yan T, et al. Cerebral blood flow predicts recovery in children with persistent post-concussion symptoms following mild traumatic brain injury. Journal of Neurotrauma. 2021 Feb.
Canada’s Testing and Screening Expert Advisory Panel [including Yan T]. Priority strategies to optimize testing and screening for COVID-19 in Canada [Internet]. Government of Canada; 2021 Jan. Available from: Government of Canada website.
Bobrovitz N*, Arora RK*, Cao C, Boucher E, Liu M, Rahim H, Donnici C, Ilincic N, Duarte N, Van Wyk J, Yan T, Penny L, Segal M, Chen J, Whelan M, Atmaja A, Rocco S, Joseph A, Clifton DA, Williamson T, Yansouni CP, Evans TG, Chevrier J, Papenburg J†, Cheng MP†. Global seroprevalence of SARS-CoV-2 antibodies: a systematic review and meta-analysis. 2020 Nov. doi:10.1101/2020.11.17.20233460
Arora RK, Rocco S, Van Wyk J, Joseph A, Atmaja A, May E, Yan T, Bobrovitz N, Chevrier J, Cheng MP, Williamson T, Buckeridge D. SeroTracker: an up-to-date SARS-CoV-2 seroprevalence dashboard. Lancet Inf Dis. 2020 Aug. Online ahead of print: https://doi.org/10.1016/S1473-3099(20)30631-9
Espenhahn S, Yan T, Godfrey K, et al. The effect of movie watching on electroencephalographic responses to tactile stimulation. Neuroimage. 2020 Jul;220:117130.
Bobrovitz N*, Arora RK*, Yan T, Rahim H, Duarte N, Boucher E, Van Wyk J, Evans TG. Lessons from a rapid systematic review of early SARS-CoV-2 serosurveys. 2020 May. doi:10.1101/2020.05.10.20097451
SeroTracker
Results: SeroTracker
Systematic review of the serology assays used in COVID-19 seroprevalence surveys
A systematic review carried out by the CITF-funded SeroTracker team, published in Vaccines, concluded that third-party or independent evaluations of serology test performance found that manufacturers report slightly higher sensitivity and specificity of their serological assays targeting SARS-CoV-2.
Natural language processing tool improves efficiency in systematic review
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.
SARS-CoV-2 seroepidemiologic studies need to improve reporting
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.
A systematic review and meta-analysis of seroprevalence of SARS-CoV-2 in Africa
This systemic review, released in a preprint that has not yet been peer reviewed, estimated that seroprevalence in Africa (due to infection or vaccination) rose from 3% in Q2 2020 to 65.1% in Q3 2021.
Global seroprevalence of SARS-CoV-2: Updated data from SeroTracker
A study carried out by SeroTracker (a CITF-funded project), in partnership with the World Health Organization, found global SARS-CoV-2 seroprevalence (due to infection or vaccination or both) was 45.2% by end of June 2021.
A systematic review and meta-analysis of seroprevalence of SARS-CoV-2 in Africa
In a systemic review published in BMJ Global Health, Dr. Rahul Arora (University of Calgary) and the CITF-funded SeroTracker team estimates that seroprevalence in Africa (due to infection or vaccination) was 65.1% in July-September 2021.
Identifying who participated in a seroprevalence study is a crucial metric
In a study published in the International Journal of Epidemiology, the CITF-funded SeroTracker team, including Dr. Rahul Arora (University of Calgary), contributed to showing that only 70% of individuals invited to participate in seroprevalence studies actually enrolled.
A report published in the Annals of the New York Academy of Sciences, prepared with the participation of the CITF-funded Serotracker team, presents the outcomes of the April 2022 Keystone symposium on the successes and challenges of the COVID-19 pandemic. Rahul Arora (University of Calgary) participated as a representative of the CITF-funded SeroTracker initiative.
Systematic review of the serology assays used in COVID-19 seroprevalence surveys
A systematic review carried out by the CITF-funded SeroTracker team, released in preprint, and not yet peer reviewed, reported that third-party or independent evaluations from manufacturers found that the manufacturers appear to overstate the sensitivity and specificity of their serological assays targeting SARS-CoV-2.
Making life easier for researchers doing systematic reviews of seroprevalence studies
Researchers at CITF-funded Serotracker present a new automated tool designed for risk of bias assessment (ROB).
Extensive review of seroprevalence provides a global panorama on immunity
CITF-funded SeroTracker carried out a living systematic review of 968 seroprevalence studies that included 9.3 million participants in 74 countries.
SeroTracker, a Canadian research group, has published the largest study to date on the global spread of SARS-CoV-2 in the journal PLOS One. The study examined antibody survey data, which were published from January to December 2020, from 9.3 million people in 74 countries and found that the number of people who had a SARS-COV-2 infection, although widely variable globally, remained fairly low in the general population.
Explore the latest seroprevalence results in Canada via SeroTracker
SeroTracker is an online tool that tracks and visualizes global COVID-19 serology testing data – testing that examines blood samples for antibodies that indicate a person has been exposed to the novel coronavirus. SeroTracker was initiated in early April 2020 to serve the COVID-19 Immunity Task Force’s need for global serological testing data as […]
SeroTracker: a global SARS-CoV-2 seroprevalence dashboard
An interdisciplinary group of health researchers, engineers, and economists has come together to gather and centralize seroprevalence data on one site, SeroTracker.
Rahul K. Arora
Rahul K. Arora
Adjunct Lecturer, Department of Community Health Sciences, University of Calgary
Doctoral Researcher and Rhodes Scholar, Institute of Biomedical Engineering, University of Oxford
Key words
seroepidemiology
surveillance
modelling
biostatistics
databases
visualization
public health
Research interests
Intersection of data science, public health, and innovation
Data-driven and technology-enabled approaches to evidence synthesis, disease surveillance, and modelling
Database development, biostatistics, and interactive data visualization
Publications
Arora RK, Rocco S, Van Wyk J, Joseph A, Atmaja A, May E, Yan T, Bobrovitz N, Chevrier J, Cheng MP, Williamson T, Buckeridge D. SeroTracker: an up-to-date SARS-CoV-2 seroprevalence dashboard. Lancet Inf Dis. Aug 2020. Online ahead of print: https://doi.org/10.1016/S1473-3099(20)30631-9
Bobrovitz N*, Arora RK*, Cao C, Boucher E, Liu M, Rahim H, Donnici C, Ilincic N, Duarte N, Van Wyk J, Yan T, Penny L, Segal M, Chen J, Whelan M, Atmaja A, Rocco S, Joseph A, Clifton DA, Williamson T, Yansouni CP, Evans TG, Chevrier J, Papenburg J†, Cheng MP†. Global seroprevalence of SARS-CoV-2 antibodies: a systematic review and meta-analysis. 2020 Nov 17. doi:10.1101/2020.11.17.20233460
World Health Organization Seroepidemiology Technical Working Group, including Arora RK. ROSES-S: Statement from the World Health Organization on the reporting of Seroepidemiologic studies for SARS-CoV-2. In press at Influenza and Other Respiratory Viruses. 2021 May.
Liu M, Arora RK, Krajden M. Rapid antigen tests for SARS-CoV-2. Canadian Medical Association Journal. 02 Mar 2021. Online ahead of print: https://doi.org/10.1503/cmaj.202827
Bobrovitz N*, Arora RK*, Yan T, Rahim H, Duarte N, Boucher E, Van Wyk J, Evans TG. Lessons from a rapid systematic review of early SARS-CoV-2 serosurveys. 2020 May 14. doi:10.1101/2020.05.10.20097451
Vincent Mooser
Vincent Mooser, MD
Chairholder of the McGill CERC in Genomic Medicine, McGill University
Contact info
vincent.mooser@mcgill.ca
Key words
Genomics, COVID, pharma, medicine, therapeutics
Research interests
Genetics
Drug development
Drug discoveries
Publications
Modeling consent in the time of COVID-19.
Knoppers BM, Beauvais MJS, Joly Y, Zawati MH, Rousseau S, Chassé M, Mooser V.
J Law Biosci. 2020 May 8;7(1):lsaa020. doi: 10.1093/jlb/lsaa020. eCollection 2020 Jan-Jun.
PMID: 32728465 Free PMC article.
The effect of angiotensin-converting enzyme levels on COVID-19 susceptibility and severity: a Mendelian randomization study.
Butler-Laporte G, Nakanishi T, Mooser V, Renieri A, Amitrano S, Zhou S, Chen Y, Forgetta V, Richards JB.
Int J Epidemiol. 2021 Mar 3;50(1):75-86. doi: 10.1093/ije/dyaa229.
PMID: 33349849 Free PMC article.
Failure to replicate the association of rare loss-of-function variants in type I IFN immunity genes with severe COVID-19.
Povysil G, Butler-Laporte G, Shang N, Weng C, Khan A, Alaamery M, Nakanishi T, Zhou S, Forgetta V, Eveleigh R, Bourgey M, Aziz N, Jones S, Knoppers B, Scherer S, Strug L, Lepage P, Ragoussis J, Bourque G, Alghamdi J, Aljawini N, Albes N, Al-Afghani HM, Alghamdi B, Almutair M, Mahmoud ES, Safie LA, Bardisy HE, Al Harthi FS, Alshareef A, Suliman BA, Alqahtani S, AlMalik A, Alrashed MM, Massadeh S, Mooser V, Lathrop M, Arabi Y, Mbarek H, Saad C, Al-Muftah W, Badji R, Al Thani A, Ismail SI, Gharavi AG, Abedalthagafi MS, Richards JB, Goldstein DB, Kiryluk K.
medRxiv. 2020 Dec 21:2020.12.18.20248226. doi: 10.1101/2020.12.18.20248226. Preprint.
PMID: 33398295 Free PMC article. Updated.
A Neanderthal OAS1 isoform protects individuals of European ancestry against COVID-19 susceptibility and severity.
Zhou S, Butler-Laporte G, Nakanishi T, Morrison DR, Afilalo J, Afilalo M, Laurent L, Pietzner M, Kerrison N, Zhao K, Brunet-Ratnasingham E, Henry D, Kimchi N, Afrasiabi Z, Rezk N, Bouab M, Petitjean L, Guzman C, Xue X, Tselios C, Vulesevic B, Adeleye O, Abdullah T, Almamlouk N, Chen Y, Chassé M, Durand M, Paterson C, Normark J, Frithiof R, Lipcsey M, Hultström M, Greenwood CMT, Zeberg H, Langenberg C, Thysell E, Pollak M, Mooser V, Forgetta V, Kaufmann DE, Richards JB.
Nat Med. 2021 Apr;27(4):659-667. doi: 10.1038/s41591-021-01281-1. Epub 2021 Feb 25.
PMID: 33633408
Biobanque québécoise de la COVID-19 (BQC19)
The Biobanque québécoise de la COVID-19 (Quebec COVID-19 Biobank) (BQC19) is a network of universities and hospitals in Quebec, led by principal investigator Dr. Vincent Mooser at McGill University. The BQC19 mission is to ensure that scientists have access to the biological materials and data necessary for their COVID-19 research to respond effectively to the pandemic’s public health challenges.
The BQC19 is recruiting close to 5,000 individuals and collecting blood samples and clinical data. Recruitment spans the full spectrum of the disease, from asymptomatic and mildly affected patients to those with severe symptoms. Control participants, that is patients who had COVID-19-like symptoms but tested negative for the disease, are also included. Participants range in age from children to elderly patients.
BQC19 is also conducting a series of analyses on the blood samples collected, including in-depth immunological, serological, proteomic and genomic analyses. All clinical and molecular data is being shared with the scientific community to help identify determinants of COVID-19 susceptibility, severity and outcome. BQC19 is part of a larger biobank network in Canada and around the world, increasing the ability of Canadian researchers to inform national and global public health science and policy, and healthcare delivery.
The BQC19 initiative will contribute directly to the efforts needed to understand the scale of infection in Canada, to inform public health policies and actions for the ongoing response to the COVID-19 pandemic, and to plan for possible future waves. Information will be shared both domestically and internationally to help mitigate the devastating impacts of the SARS-CoV-2 virus.
Biobanque québécoise de la COVID-19 (BQC19)
Identification of Important genetic indicators of COVID-19 outcomes
Research carried out at the CITF-funded Biobanque québécoise de la COVID-19 (BQC19), published in PLOS Genetics by Drs. Guillaume Butler-Laporte, Brent Richards, and Vincent Mooser (McGill University), showed that those with a rare deleterious variant (disease causing variant) in the SARS-CoV-2 sensor toll-like receptor TLR7 gene (on chromosome X in the host) were associated with a 5.3-fold increase in severe disease.
HostSeq: A Canadian consortium collecting genetic data to identify factors associated with COVID-19
The HostSeq platform, established in April 2020, is a national collaboration of population-based studies investigating the genetic risk factors behind SARS-CoV-2 infection and health outcomes associated with it.
Blood circulating protein differences among individuals with acute COVD-19
In a publication in Clinical Proteomics led by Drs. Brent Richards and Guillaume Butler-Laporte (McGill University), CITF funded researcher Dr. Daniel Kaufmann (Université de Montréal) and Dr. Vincent Mooser (McGill University, former director of the Biobanque québécoise de la COVID-19 (BQC19)) determined that severe COVID-19 is associated with significant changes in 69 immune-related proteins.
Kumanan Wilson
Kumanan Wilson
Professor, Department of Medicine, University of Ottawa
Researcher, Bruyère Research Institute
Principal Investigator, Clinical Epidemiology Program, Ottawa Hospital Research Institute
Key words
Immunization
Policy
digital health
technology
pandemic preparedness
Research interests
Immunization
health policy
digital health
Publications
Flood CM, Thomas B, Wilson K. Mandatory vaccination for health care workers: an analysis of law and policy. CMAJ. 2021 Jan 19:cmaj.202755. doi: 10.1503/cmaj.202755. Epub ahead of print. PMID: 33468521.
Flood CM, Krishnamurthy V, Wilson K. Please share your vaccination certificate. Policy Options. December 11, 2020.
https://policyoptions.irpp.org/magazines/december-2020/please-show-your-vaccination-certificate/
Wilson K. The Big Debate: Should those with immunity get a COVID-19 digital passport? Toronto Star. May 12, 2020.
Immunity Passports for COVID-19: Scientific, Ethical, Policy and Design Implications
Much ink has been spilled on who should get priority access to vaccines. Less attention has been given to whether governments or the private sector will require individuals to provide proof of vaccination and, if so, in what contexts.
Some countries are already implementing immunity passports or certificates. These could be especially valuable for identifying immune front-line workers, which could help reduce the spread of disease. This approach might also offer a partial solution to lockdowns. However, it is fraught with scientific, ethical, legal, and design concerns.
Policymakers must lay out clear rules for how these immunity passports would be rolled out and regulated, how they are designed (particularly, security and privacy features), and how they are deployed across the public and private sectors as the science evolves — in a way that judicially balances adverse impacts on individuals with public health benefits.
Our study is evaluating the potential use of an immunity passport in Canada. We are examining the current international use and studying the specific implications for Canada. We will provide guidance on the potential design of an effective digital tool to manage immunity tracking, as the dynamic nature of the science is best suited to digital certification solutions.
Our findings will inform the Canadian public health response, as well as local, provincial, and national decision making. Our project is an important step in carefully examining the complex issue of immunity passports in a multidisciplinary and unbiased manner.
Results: Immunity Passports for COVID-19: Scientific, Ethical, Policy and Design Implications
A commentary by a CITF-funded researcher, published in Intelligence Memos, explores the extent to which privacy laws restrict businesses’ ability to verify an individual’s vaccination status.
Understanding human rights legal considerations in vaccination mandates for businesses
A commentary by a CITF-funded researcher, published by the C.D. Howe Institute, discusses the differences in implementing vaccination mandates in businesses vs. in government sectors.
There are four fundamental choices for the design of vaccine passport systems
A commentary by a CITF-funded researcher, published by C.D. Howe Institute, highlights four fundamental choices for the design of vaccine passport systems that bear upon potential privacy considerations for Canadians.
Each booster dose increases vaccine effectiveness against all Omicron subvariants
A CITF-funded study, published in Clinical Infectious Diseases, provided evidence that protection provided by COVID-19 vaccines and/or prior SARS-CoV-2 infections against severe outcomes is reduced when immune evasive SARS-CoV-2 variants and subvariants emerge.
A CITF-funded study, published in JAMA Pediatrics, reported that maternal mRNA COVID-19 vaccination during pregnancy was associated with lower risks of severe neonatal morbidity, neonatal death, and neonatal intensive care unit (NICU) admission.
Vaccine passports are meant to protect the unvaccinated population
A CITF-funded study, published by the C.D. Howe Institute, underscored that vaccine passports are aimed at protecting unvaccinated people or people who cannot be vaccinated from the risk of serious illness from COVID-19.
Educating adults about COVID-19 vaccines is essential to promote vaccine confidence
A CITF-funded review, published in Campbell Systematic Reviews, found that among various strategies for promoting vaccine confidence, educational interventions were introduced to support individuals in their vaccine decisions by building COVID-19 vaccine knowledge and confidence. Group-based and formal presentations were the most frequently used.
In a paper published in JAMA (Journal of the American Medical Association), CITF-funded researchers Drs. Deshayne Fell and Kumanan Wilson of the University of Ottawa and Dr. Jeffrey Kwong from the University of Toronto and colleagues found that COVID-19 vaccination was not significantly associated with an increased risk of adverse pregnancy outcomes.
Effectiveness of COVID-19 vaccines against VOCs in Canada
The race to vaccinate the world against SARS-CoV-2 became more urgent as variants of concern (VOCs) began to emerge.
A comprehensive review of international vaccine certificate programs for COVID-19
Vaccine certificates or "passports" are becoming more commonplace, with access to restaurants, event venues, and even workplaces increasingly dependent on proof of vaccination against COVID-19.
Equity and design are key to successful vaccine passport programs in Canada
Commonly called vaccine passports, immunization records or documents indicating vaccination status will be important as certain parts of the world begin to reopen.
Passport to normal: CITF researcher Kumanan Wilson comments on the future of immunity passports
With vaccine coverage on the horizon, many people are starting to think about how to document immunization.