“These data suggest that reinfection with SARS-CoV-2 is rare and occurs in less than 1% of individuals...”











https://twitter.com/EricTopol/status/1372329717928325125 …
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What we really need is a longitudinal cohort of the same individuals that has been followed over time, with a non-probabilistic sampling method to minimize selection bias, and who are tested (say) twice a month regardless of symptoms. But that is a really hard ask
So I'm not saying the researchers could've done a better study using the data at hand, because I love this piece of research, but that to really answer the question we kind of need a different study design altogether
I’m not seeing the selection bias in free-for-all testing but agree on looking longitudinal. But “they need more longitudinal data” can apply to most studies. 
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