I'm not saying they have it but it's theoretically possible they could: https://www.gq.com/story/julia-ioffe-false-negative-covid-testing
As the old saying goes - 99% of the population have a 99% chance of not fully understanding probability theory...
@Brommers started
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I'm not saying they have it but it's theoretically possible they could:
https://www.gq.com/story/julia-ioffe-false-negative-covid-testing