The U.K. Coronavirus Mutation Is Worrying but Not Terrifying

A new mutated form of the novel coronavirus that appears more transmissible than the original has raised alarm in the U.K. and around the world. It does not appear to cause more severe disease, and the newly available vaccines do seem to protect people against it. Yet on December 19—after an announcement that the variant, dubbed B.1.1.7, had suddenly accumulated 17 mutations and was spreading rapidly in the U.K.—the nation’s prime minister Boris Johnson announced stricter lockdowns there. And numerous European countries have halted travel from that nation.