About 8,000 blood test kits and surveys are being mailed to Nova Scotia households as part of a national study to assess the pandemic’s health impacts and potential long-term effects of the virus.
“This will give us a better view overall of how Canadians have fared and what they’re bringing forward into the future and how best can you then anticipate what services and supports might be needed,” COVID-19 Immunity Task Force co-chairperson Dr. Catherine Hankins said in an interview.
The survey is being sent to 100,000 Canadians in 10 provinces this spring. The first wave of 2,494 survey and test kits were sent to randomly selected Nova Scotia households in April. Another 2,718 were sent on May 10, and the final 2,718 will be mailed out next month.
“We need to get a good feeling for how many Canadians actually got COVID… some people may not even have been aware that they actually did have an asymptomatic infection at one point,” Hankins said.
“This gives us a much better idea of how much immunity there is across the country and gets us in a better position to then inform policies to do with vaccines like whether additional doses are needed, and if so, for whom. Because this is not really over.”
Led by Statistics Canada, the COVID-19 Immunity Task Force (CITF) and the Public Health Agency of Canada, the Canadian COVID-19 Antibody and Health Survey will include details for filling out an online questionnaire and finger-prick dried blood spot (DBS) test kits.
Those blood spot tests will help researchers better understand how many Canadian adults 18 and older have infection-acquired or vaccine-induced antibodies (or both) to the SARS-CoV-2 virus.
“People now, perhaps more than last year, really want to know, ‘Am I showing antibodies?’ It (DBS test) will tell you if you have vaccine-induced antibodies or infection-acquired antibodies, or if you have both, which would mean a hybrid immunity,” Hankins said.
“If you get chosen, you’re actually quite lucky because you’re going to be able to get some information about your own status that is not readily available.”
Hankins said the dried blood spot test will also help researchers better correlate chronic symptoms with a COVID-19 infection.
“If we can see the antibodies, then that confirms that while your symptoms may not be related to COVID, at least it shows that you did have it,” she said. “It strengthens the data in the overall survey itself for long-COVID.”
The latest wave of the survey mailed out this month will include a PCR saliva test to check for active infections. This will help researchers better estimate the number of Canadian adults who have or have had a SARS-CoV-2 infection during a time when there’s been a sharp nationwide decline in PCR testing.
“The task force is very interested in the immunity component of this, so how many people actually have antibodies,” Hankins said.
“And with the saliva specimen, how many people at this point in time have infections going on at the time they do the saliva sample? It would give us a better idea of how much asymptomatic infection is going on where people don’t even use an antigen test because they’re not symptomatic.”
More than a long-COVID survey
While the study began as a survey looking at how many Canadians were infected and either got over the illness or have lingering symptoms, Hankins said it’s more than a long-COVID survey. She described it as a look at SARS-CoV-2 exposure and the experiences of patients with ongoing symptoms and their challenges accessing health care.
“Any viral infection can lead to chronic symptoms that take a while to resolve, so it’s important to try to sort out, are these symptoms actually related directly to COVID? Are they related to two years of stress,” Hankins said, adding that even if symptoms aren’t COVID-related, patients still need help.
“We’re seeing a slightly higher incidence (of long-COVID) in women than men, so what is that about? Everybody’s been stressed, but there’s been additional stress for women and it’s going to be really important to try to sort that out.”
Hankins, who’s also a professor at McGill University’s School of Population and Global Health, said the survey and test kits have been designed to provide the most representative sample of the Canadian population 18 years and older.
That’s why it’s critical that if you’ve received one of the survey kits in the mail, you don’t hand it over to someone else in your household.
“You’re chosen representing your demographic and your geography, so your age, your sex, etc., so you’re representing other people of that same age, sex and geography, you’re kind of the sentinel person,” Hankins said.
‘Only a 19.1% participation rate so far’
Pandemic-related changes in the way health care was delivered, particularly in the early days, led to declines in screening for things like cancer and even simple blood pressure checks. Hankins said this survey will also help paint a picture of how potential late diagnoses might be impacting Canadians and their prognosis for various diseases.
“There’s a lot to get caught up on, waiting lists all over the place depending on what it is you’re trying to get, and so many health care workers got sick and remain sick, are still sick,” she said.
“We’re not at full capacity yet, I don’t think… Everybody wants this to be over and it’s so critical that we actually look to see how best we can design our health services to support people going forward.”
The first batch of survey and test kits sent to Nova Scotians in April have so far only garnered a 19.1% participation rate. Response was highest in British Columbia at 20.1%.
Hankins said anyone who received the first survey kit in April but has yet to complete it is being encouraged to do so.
This latest round of surveys is considered a second cycle of the antibody and health survey. The first cycle was conducted in late 2020 and early 2021 when 3,600 Nova Scotians were among 48,000 Canadians who were sent blood test kits and surveys.