FAQ

The goal of the Ab-C is to provide crucial information on the course of the COVID-19 pandemic in Canada over time, with periodic survey questionnaires and blood testing for COVID-19 antibodies among a representative sample of adult Canadians. The information generated by the study can help frame the public health response to COVID-19 and ultimately improve the well-being of Canadians.

All participants who completed the online survey about their experience with COVID-19 during Phase 1 of the study—whether or not they contributed a blood sample—will be invited to participate in future phases. Each phase will be similar, starting with the online questionnaire followed by home blood collection. The questions asked are likely to change somewhat based on new information about the virus and its effects. There may also be some additions, for instance, a home saliva collection in addition to blood, in addition to special requests for small studies within the whole population. Participating in one part of the study does not obligate anyone to continue, and all participation is of value. In each phase, blood spots will be analyzed using a high performing laboratory test to determine whether antibodies to COVID-19 are present. Test results will be provided back to participants as quickly as possible. We are confident that results in future phases can be processed much more quickly than in Phase 1.

Ab-C participants may opt to provide their provincial health card number so that the information contained in provincial health databases (e.g., billings for visits to doctors, hospital admissions, medication prescriptions, etc.) can be linked to study data. This is entirely voluntary, and no data will be accessed without explicit permission.

Participants are also asked for permission to store any unused dried blood samples to answer questions about COVID-19 in the future. We do not yet know which factors might be examined, as research on COVID-19 is still emerging, but this future work will be done entirely anonymously, without linkage to a participant’s identity. Any future testing on the samples will be done only for research purposes and participants will not be offered individual results. Important results will be published in the scientific literature and explained in issues of the Ab-C Newsletter.

DBS is a blood sample obtained by a pricking a finger with a lancet and depositing drops of blood on special filter paper.

Participants who agree to collect DBS for Ab-C are mailed a complete package that includes an informed consent document; the collection kit (lancets, filter paper, bandages, etc.); complete instructions; and a postage-paid return envelope. The process does not require any training.

The dried blood spot collection kit contains 2 antiseptic wipes, 1 packet of sterile gauze, 2 small bandages, 2 lancets, 1 blood sample collection card, 1 foil (Mylar) zip-lock pouch with drying agent, and 1 plastic return envelope. In addition, you will receive printed instructions and a consent card with information on how to complete the online consent form.



Video instructions can be seen on the Ab-C website “For Participants” page (in the menu above).

The blood will be analyzed using the best available assays (laboratory tests that measure the presence and amount of a substance). The laboratory results indicate how likely it is that participants were exposed to the virus by detecting COVID-19 antibodies (markers of immune response) in their blood.

This is not a diagnostic test and cannot be used to inform clinical decisions. The test does not indicate if someone has or had the virus, or have immunity to it.

The Ab-C received contact information from the Angus Reid Forum, with whom the Ab-C team is partnering to conduct this vital research. During the Angus Reid Forum polling about experiences with COVID-19, participants provided consent for the Ab-C team to make contact. The Angus Reid organization transferred contact details to us using a secure network connection.

We anticipate that 10-14,000 adults aged 18 or older in Canada will participate in this study.

If you are enrolled in the study, you have already completed the Angus Reid poll, for which we thank you. You will now be asked to take a small sample of blood using safe, well-tested procedures (some diabetic patients do this at home every day). Then, send us the sample in a safe, tamper-proof postage-paid envelope and fill in the consent form online at www.abcstudy.ca using the secure personal code printed on your consent card).

We will return the results of the test to you via email. The results will indicate a 'highly likely' OR 'somewhat likely' OR 'unlikely' antibody response. We will not be able to tell you when or how you may have been infected.

Please note that the results are not to be used for any clinical decisions and do not prove that you have immunity to COVID-19. Every Canadian will need to continue following federal and public health guidelines on how to protect themselves from COVID-19 and how to protect others in case one is exposed or infected.

When we contact you with the results, we will ask you for permission to re-contact you at least once in the future, to possibly re-test using the same procedures to find out if your infection status might have changed.

There are no medical risks from participating in this study. Some people may experience very minor discomfort from the finger prick to collect blood. The lancet used to make the small cut in your skin cannot be reused. The needle is sharp, so be careful with it around others, especially children; and we recommend that all this testing be done away from others. COVID-19 is NOT transmitted through blood (only through lung or breathing droplets) so there is virtually no risk that anyone else in the house who touches a participant’s blood will be at risk from COVID-19, should the participant be infected. However, other infections can be spread through blood, so participants should protect blood from being touched by others while drying.

All usual precautions are in place to protect personal information and we will maintain vigilance to ensure the privacy of all participants.

Participants get no direct health benefit from participating in Ab-C other than finding out the likelihood of past COVID-19 infection. The value of the study lies in informing the Canadian public, including the public health establishment, of the status of Canadians with regard to the virus.

Participating in the Ab-C Study does not replace the Canadian government guidelines for COVID-19 reporting and testing. Anyone with symptoms suggestive of COVID-19 should follow national guidelines, including self-isolation completing the self-assessment at https://ca.thrive.health/covid19/en.

All Ab-C participants are contributing crucial information to combat this extraordinary epidemic which has affected the lives of so many around the world. This research will play a key role in helping to shape the public health and control responses to COVID-19 in Canada and internationally.

After consent is obtained, participants will be mailed a self-administered collection kit. We will also be in touch with blood test results as soon as they are available. We may also ask some participants for permission to contact them about follow-up studies.

Participants may choose to end their participation at any time without having to provide a reason. However, if you choose to end your participation before completing the study, you will still be asked to send the home kit unused back to the study centre using the postage-paid envelope provided.

Choosing to withdraw will have no effect on your current or future medical treatment or health care. Participants who withdraw from the study are encouraged to contact the study coordinator at 1 833-TEST-ABC (837-8222) or AbCstudy@unityhealth.to. Information collected before study withdrawal will still be used in analyzing study results. Participants wishing to have their samples destroyed should notify us. After withdrawal from the study, no new information of further testing will be done without explicit permission from the participant.

Participation in this study does not involve additional costs to participants. No travel is required, as all study procedures take place in the home. All materials are sent by mail, and the return mailing envelope is postage prepaid.

If a participant becomes sick or injured as a direct result of participation in this study, medical care will be provided. Financial compensation for such things as lost wages, disability, or discomfort due to this type of injury is very rare and not routinely available. By signing the consent form, you do not give up any of your legal rights. We stress, however, that participation in this study carries virtually no medical risk.

No payment is made by the Ab-C team. Angus Reid organization will provide 'Points' through their existing program.

The Ab-C Study considers the public to be its most valuable partner in research. Thus, protecting privacy and meeting participant expectations in this regard is a priority. The Ab-C Study team, the different institutions involved, and the Ab-C researchers and staff are all committed to ensuring that privacy and confidentiality are always respected. We have developed a privacy policy consistent with Canadian Institute of Health Research guidelines, our hospital's Research Ethics Board, and other approved studies in Canada.

Several mechanisms are in place to ensure confidentially. The most important are:

' The collected data are stored using a unique code and not names or other identifying information. The identifying information is stored at St. Michael's Hospital (SMH) in a secure and separate database.
' When data are collected, they are automatically encrypted and transmitted with the unique ID number through a secure VPN to the central database at SMH.
' All staff involved in Ab-C are bound by a strict confidentiality agreement that prohibits them from using any information for any purpose other than what is required for their specific tasks. We maintain a log of dates and times that personnel access the identifiers.
' Data and samples are stored in highly controlled access areas where only special card holders are able to enter; a log of all entries/exits into these restricted premises is kept.
' The workstations through which Ab-C staff are able to access the collected data (e.g., for quality control purposes) are not connected to internet, and they are password protected.
' The Ab-C will grant access only for ethically and scientifically approved future research. Approval is granted by the Ab-C Scientific Committee followed by approval from a Research Ethics Board. Approved researchers must sign confidentiality and data access agreements, which bind all users to the terms and conditions set out by SMH. We will not release any personal or identifying information to external researchers.
' The Ab-C study design has been reviewed by the Research Ethics Board of Unity Health Toronto (St. Michael's Hospital). As part of the ethics process, any changes to the Ab-C are reviewed annually.

Ab-C staff: A limited number of Ab-C staff and partner laboratories have access to participant data and samples for purposes of developing the database and doing quality control tests. A more limited number of staff have access to identifying information for purposes of contacting participants in the future, for updating participant information, for linking with other provincial health databases (if consent was provided), or for registering a withdrawal. Identifying information will not be released to a non-research related third party without participant consent or unless it is required by a valid court order or by law.

Researchers: Researchers in public institutions in Canada and other countries can request access to de-identified study data (but not personal information, such as names or addresses) to conduct specific research projects. Approval is granted by the Ab-C Scientific Committee and must also be approved by a Research Ethics Board. Approved researchers must sign confidentiality and data access agreements, which bind all users to the terms and conditions, set out by the Ab-C. Researchers from private businesses will not have direct access to personalized data and samples, but may be part of a research team.

Participants can always request access to their own information. In the very unlikely event that we are required by law to provide a participant’s information to a third party, we would inform the participant before providing it.

Participants have the right to receive all information that could help them make a decision about participating in this study. They also have the right to ask questions and receive complete answers about this study and the rights of research participants, both before entering the study and throughout its course.

The investigators have are no conflicts of interest related to this study.

For participants who provide provincial health card numbers and have authorized the study to access provincial health databases, the Ab-C team will abide by the laws and practices of each province in accessing specific information needed for any specific study question.

a) All entities forming part of the overall governance structure of the Ab-C;
b) The principal investigators, co-investigators, institutions and all staff responsible for collecting data and/or samples for inclusion into the Ab-C research platform;
c) All researchers seeking access to Ab-C data for specific research projects, and as approved by relevant research ethics boards and the Ab-C Scientific Committee. These individuals are held accountable for compliance either directly (e.g. through terms and conditions in data sharing agreements, user agreements, and confidentiality agreements).

Unfortunately, we cannot enroll other family members unless they have been already selected to participate as part of the Angus Reid Forum. This is to make sure that we take as "random" a snapshot of adult Canadians as possible. However, family members can join the Angus Reid Forum, which could make them eligible to participate in a future survey.

A personal code can be found on the back of the consent information card in the kit. That is the only code that should be used on the online consent form and it cannot be seen in any other part of the kit. It is an 8-character secure personal code.

Results from Phase 3 are being sent out in November.
They are sent as pdf email attachments.

In Phase 1, a highly likely or somewhat likely result on the antibody test means that it is more likely than not that a person was infected with the COVID-19 virus earlier in 2020, but we can’t be absolutely sure. In Phase 2 onwards, if you received a COVID vaccine before taking the blood sample, these result categories typically indicate an antibody response to the vaccination. If you were unvaccinated, it indicates a likely past infection with the COVID-19 virus. It does not mean that you are currently infected. It also is not a guarantee that you are immune from a re-infection. That means you should take all the precautions advised by your province against COVID and follow the latest guidelines.

The federal and provincial guidelines for COVID vaccination for those with documented past infection based on antibody testing are not yet issued. This is a topic where more research is needed, and as that is collected, the Public Health Agency of Canada and the provincial health authorities will issue guidelines. Once they are issued, we will include links to them on this page.

No. The antibody test reflects past infection only, and provides no information on possible current infections Anyone with new symptoms should consult provincial guidelines to see if a PCR test for active infection is recommended.

No. A negative test does not equal immunity or protection against the virus in any way. This is true also even for someone who tested negative in a house where a household member was infected.

The Ab-C study is a research study on population health and the results are not helpful for clinical decisions, so they need not trigger a discussion with a physician.

All tests have error rates, and while we tried to minimize this in the antibody assay, we cannot exclude false negative results. We think false negatives are rare, however. The symptoms of COVID-19 have substantial overlap with other viruses, which may be an alternate explanation.

Yes. We will be asking people about their vaccination status and encourage all those invited to the study to participate, regardless of whether they have gotten the vaccine or not.

There are two possible explanations. The most likely is that you were actually infected earlier in the pandemic and your immune system responded. Your antibodies were detected in the first test, but by the time of the later test, the antibody levels had declined to a point below the test positive cut-off. It doesn’t change your infection history, nor does it mean that you would not necessarily be protected if exposed. The second explanation is that one of your results was classified as positive, when in fact you were negative. This does occur in all lab tests. Given that COVID antibody assays are new, these are also expected, albeit rarely with the tests we are using. We hope you will continue to participate and we can gain more insight from an additional test.

The most likely explanations are that you received a COVID vaccine before taking your second blood sample, or between your first and second tests, you became infected with the virus that causes COVID-19. If this comes as a surprise, you were probably one of the people who had an asymptomatic case; in Phase 1, people who did not report one of our key symptoms made up 30% of those who were identified as highly or somewhat likely to have been infected.

It is uncommon for people who have been vaccinated to not have a detectable antibody response, except for people who have weakened immune systems because of medical conditions or medications. The result could be a “false negative” or may reflect a poor immune response. If you have concerns about the results, please discuss them with your healthcare provider.

Vaccination information in the results comes from your most recent response to an Ab-C study survey through the Angus Reid Forum; if you have been vaccinated since the last survey, your vaccination information may not yet have been updated. The Angus Reid Forum will be sending out a new survey that asks you to confirm/add your vaccination information. This is the best way to update this information for the study, as it allows us to link the data directly to your study record in the correct format.

If an antibody response was detected, “probable source” indicates whether the results suggest that the antibodies were induced by vaccination against COVID-19 (“Vaccine”), infection with SARS-CoV-2 (“Infection”), or both (“Infection and vaccine”).
If an antibody response was detected but the probable source could not be determined from the results, the probable source is “unknown”.
If your antibody result was “unlikely” or your sample did not have sufficient quantity for testing, the probable source is “N. A.”.

No; based on the timing of the sample collections, if your latest test result has changed to “Infection” or “Infection and vaccine”, the most likely cause is an Omicron infection; however, this test does not identify a specific variant or Omicron subvariant (e.g. BA.1, BA.2).