How British Scientists Found the More Infectious Coronavirus Variant - The New York Times

Back in March, researchers decided to routinely record the genetic sequences of the virus they found, giving them a powerful tool for tracking mutations.

Steven Kemp, an infectious disease expert, had been scanning a global library of coronavirus genomes.

He was studying how the virus had mutated in the lungs of a patient struggling to shake a raging infection in a nearby Cambridge hospital, and wanted to know if those changes would turn up in other people.

Kemp made a startling match: Some of the same mutations detected in the patient, along with other changes, were appearing again and again in newly infected people, mostly in Britain.

The two researchers did not yet know it, but they had found a new, highly contagious coronavirus variant that has since stampeded across Britain, shaken scientists’ understanding of the virus and threatened to set back the global recovery from the pandemic.

For nearly a year, scientists had observed only incremental changes in the coronavirus, and expected more of the same.

The country produces half the world’s inventory of coronavirus genomes, providing an unparalleled view of how the virus changes, and how people brought it into Britain last year and are now carrying the variant out.

But Britain sounded an alarm for the world, allowing countries to close their borders and start frantically searching for a variant they otherwise might not have noticed for months.

Labs around Britain, after testing swabs for the virus, send the leftover material in refrigerated vans to the Wellcome Sanger Institute, a genomics lab, where they are stored in cavernous freezers.

The United States, with five times as many people, has sequenced about 74,000 genomes.

The campaign took shape on March 4, before 100 coronavirus infections had been found in Britain, when a Cambridge microbiologist, Sharon Peacock, sent a flurry of emails to British genomicists, asking each: “Can you call me please.”.

But the mutations in his virus eventually supplied scientists with a leading theory for how the British variant originated: by eluding the immune defenses of someone like the Cambridge patient who had a weakened immune system and a long-lasting infection.

Then in late November, abruptly, he noticed many genomes, mostly from Britain, that had those mutations and a host of others that could change how the virus entered human cells.

Eventually, British scientists detected 23 mutations that distinguished these genomes from the earliest known version in Wuhan, China — enough to be a considered a new variant, since labeled B.1.1.7.

Looking back through their databases, scientists discovered that it had first been collected in September, and had spread as people returned to offices and patronized restaurants and pubs at the government’s urging.

22, government scientists said that strict measures, including school closures, were needed to suppress the variant.

American health officials warned on Friday that the British variant could be the dominant source of infection in the United States by March.

Kemp have begun using blood serum from vaccinated people to determine if the variant may weaken the potency of the vaccines