As Americans began to stir in the early morning hours of Thanksgiving Day 2021, a rapt international press corps was listening as a pony-tailed scientist in South Africa announced the identification of a worrisome new SARS-CoV-2 variant. Tulio de Oliveira, a Brazilian-born bioinformatician, explained that many of the variant's dozens of mutations might make it more immune evasive and contagious-and that it was spreading "very fast" in South Africa.
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