‘Like Wartime’: Canadian Companies Unite to Start Mass Virus Testing

The group focused on antigen tests because of their speed, price and utility: They can produce results in minutes, don’t require a laboratory and, in Canada, can cost between $5 and about $20.

But they are less accurate, and produce more false negatives, than the gold-standard polymerase chain reaction, or P.C.R. tests, which can cost 20 times as much. The three antigen tests approved for use in Canada flag between 84 percent and 96.7 percent of the people infected with the virus.

In Britain, antigen tests used in a mass testing campaign identified just two-fifths of the coronavirus cases detected by P.C.R. tests.

For that reason, many experts in Canada and elsewhere initially argued it was wiser to expand P.C.R. testing. But, as the pandemic stretched on and the country failed to reach its testing targets, that thinking has changed, said Dr. Irfan Dhalla, co-chairman of the Canadian advisory panel on testing and screening for Covid-19, which recommended the country increase the use of rapid tests.

“A rapid antigen test is clearly better than no test at all, as long as it is not used as a free pass,” Dr. Dhalla said. “Whether it’s a workplace or a school, you still have to wear a mask and you still have to physically distance as much as you can.”

Consortium members hope in the long run that the testing program will help reduce infection rates enough to permit a return to crowded restaurants and boardroom meetings. But in the meantime, they plan on using the tests as an added layer of protection — on top of wearing masks, engaging in social distancing and pre-screening employees so those with symptoms stay home.

Article source: https://www.nytimes.com/2021/01/30/world/americas/canada-coronavirus-rapid-test.html