The new coronavirus strain has been discovered in Canada, as public health leaders warn that the United States may have failed to detect the most infectious variant.
Two cases of the Sars-Cov-2 variant first sequenced in the United Kingdom were identified in Canada on Saturday, after being found in European countries, Japan and Australia. Canadian patients have not traveled to the UK, which makes it likely that the new strain is spreading through the community.
Dr Barbara Yaffe, an associate chief medical officer from Ontario, said the discovery “further reinforces the need for Ontarians to stay at home as long as possible” as the Canadian province began closing on Saturday.
The new strain – which some scientists fear may be up to 70 percent more transmissible – has yet to be discovered in the United States, prompting the Trump administration to demand that visitors from the UK take the test starting on Monday.
But the United States Centers for Disease Control and Prevention warned that the country had not done enough genetic sequencing of the virus to be sure it was no longer circulating.
“Given the small fraction of infections in the US that have been sequenced, the variant could already be in the United States without being detected,” said the agency on its website.
The United States sequenced only the virus that infected about 51,000 cases of the 17 million people who tested positive for Covid-19, said the CDC. In contrast, the United Kingdom conducted much more extensive genomic surveillance, sequencing almost 10 percent of all positive tests, according to the latest analysis from the Covid-19 Genomics UK Consortium, which used data until mid-November.
Angela Rasmussen, a virologist at Georgetown University, said the travel restrictions were “a little too late”.
“It is likely that this variant is already here and we just haven’t detected it yet,” she tweeted. “Why? The sorry state of genomic surveillance in the US. This is a major weakness that we need to correct.”
The new variant of the virus appeared in Kent, in southeastern England, in late September. In the week ending December 9, it accounted for 62% of infections in London.
Dr. Anthony Fauci, the top infectious disease physician in the United States, said the mutations had always been “worrying”, but he tried to calm the American public by saying there was no evidence that it appeared to lead to a more serious illness.
“The other question is, does it escape the protection induced by the vaccines we are currently using? And, according to our British colleagues, it doesn’t seem to be the case, ”he told CNN. state of the Union on Sunday.