By far, Quebec has seen the most confirmed COVID-19 cases in Canada, but does that number paint the real picture?
Only a fraction of the population has actually been tested for the infection, but antibody testing may soon give us a better idea of how widely the coronavirus has spread.
“What these sero-prevalence studies will tell is how many people not necessarily got sick, but how many people have seen the virus, developed antibodies against the virus,” explained Andres Finzi, the Canada Research Chair in Retroviral Entry and a researcher at the University of Montreal Hospital Centre.
Evidence of your immune system’s response is found in your blood, so a partnership between public health officials and Quebec’s blood donation agency Hema-Quebec became a natural fit.
“It became quite obvious very rapidly that this would be a very interesting setup to do, a population-based sero-survey by looking at blood donors,” said Dr. Marc Germain, Hema-Quebec’s vice-president of medical affairs and innovation.
For more than two months, Hema-Quebec has been asking blood donors across the province if they wanted to be tested for COVID-19 antibodies. More than 7,000 chose to participate.
“We picked the clinics according to our sampling strategy, and donors couldn’t know in advance if the date he or she wanted to donate, there would be this study happening,” Germain explained.
The goal was to get a realistic sampling of how many people in Quebec have had the virus, and how many were asymptomatic. They tested more samples in Montreal, because Montreal had the most cases.
The results should be out in the next few weeks.
Scientists say that just because someone has COVID-19 antibodies in their blood does not mean they’re immune to the novel coronavirus.
“We don’t know yet whether the presence of antibodies is sufficient to indicate that someone is protected or not,” Finzi said.
While Hema-Quebec’s first antibody study is over, they may do more if a second wave arrives.