Researchers from a University of Montreal estimate that the prevalence of the COVID-19 virus in Canada is much higher than what is reported.
In Ontario and Quebec alone, economists at the University of Montreal (UdeM) say that almost half a million people are infected with the virus, about 14 times more than the official number.
Researchers say the differences in testing between different provinces have added to the uncertainty surrounding the actual number of cases in the country. Quebec had almost 9,000 more cases than Ontario on April 22, but the researchers noted that Quebec was much more aggressive with its tests.
“Do the differences in the confirmed cases reflect true prevalence or are they the result of different test standards?” “Said UdeM economist Joshua Lewis, who worked on the analysis with a UdeM colleague, Raphael Godefroy, and David Benatia of the Institut Polytechnique de Paris.
The trio used a statistical technique to calculate what they say is a more accurate number of cases in the central provinces by adapting a study they used to analyze the prevalence of COVID-19 in the United States.
They found that on April 22, the number of infections in Quebec was just over 255,000 – 12 times more than what was declared by the authorities at the time; and more than 220,000 in Ontario – 18 times more.
“Our results show how differences in testing standards between provinces can greatly mask the true severity of the epidemic,” said Lewis. “The actual number of infections in Quebec and Ontario is remarkably similar despite the fact that Quebec has almost twice as many officially reported cases.”
Researchers have said that public health needs accurate and up-to-date data to adjust its response as governments cope with the ongoing pandemic. To do this, they suggest that the test be extended to the general population – this would help stop community transmission without notice and help identify what they say is a significant amount of people who might have a level of immunity against virus.
“How widespread is COVID-19 in the general population, really?” Said Lewis. “This is what we need to get a much better picture of. This is important for policy makers who have to make difficult choices about how long it will cost to impose costly social distancing measures. “
Lewis said precise numbers will also help Canadians decide what personal precautions to take to protect themselves from the virus.
“Whenever we venture to the supermarket or for a walk, we worry about crossing paths with someone who has the virus,” he said. “The question is, should we, and to what extent?
In the past week, Quebec Premier François Legault announced the reopening of elementary schools, daycare centers, the construction and manufacturing sectors and certain retail stores, starting May 11.