Razor-blade sore throats: meet Nimbus and Stratus, the new Covid variants

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COVID is quietly surging in the U.S. and the U.K., driven by emerging variants NB.1.8.1 (”Nimbus”) and XFG (”Stratus”). Both are found in national wastewater systems, turning up in traveler screenings and state labs. Health officials warn that NB.1.8.1 has surged from ~15 % to ~37 % of estimated U.S. cases since late May, putt…