Variant Hunters Race to Find New Strains Where Testing Lags | WIRED

Variant Hunters Race to Find New Strains Where Testing Lags | WIRED What has shocked researchers about the variant identified in the Tanzanian travelers is that it is so distantly related to other variants of concern. It’s a member of the so-called “A lineage”—sometimes dubbed the “19 lineage” since it appeared in 2019—and is the closest known relative to the virus that first spilled into humans. “My postdoc sent me a Slack message saying, ‘WTF the A lineage??’” says Bill Hanage, an epidemiologist at Harvard University who studies viral evolution. Variants of the A lineage are still picked up from time to time, but by early 2020, most of them had been outcompeted by members of the still-reigning B lineage. The finding underlines the power of human networks in how viruses spread, Hanage adds. B-lineage variants clearly acquired mutations that made them fit to spread across the world, but what if they also got boosted by luck? It’s possible that viruses of the B lineage simply happened to take root early on in densely populated places like New York City and Italy, and from there they took over the world.