[bvinc]

This is really good news. Whenever I see people talking about if previously infected people should be vaccinated, they always mention how we don't know how long protection lasts for previously infected people. This study includes this section:

    Duration of protection

    This study was not specifically designed to determine the duration of protection afforded by natural infection, but for the previously infected subjects the median duration since prior infection was 143 days (IQR 76 – 179 days), and no one had SARS-CoV-2 infection over the following five months, suggesting that SARS-CoV-2 infection may provide protection against reinfection for 10 months or longer.

[alok-g]

See also:

Had COVID? You’ll probably make antibodies for a lifetime https://www.nature.com/articles/d41586-021-01442-9

[jquery]

Most “previously infected” people were absolutely not infected at all. If this study involved self-reported previously infected and not confirmed PCR, the results would be very different.

[jobigoud]

Isn't there also a lot of people that self report as having had covid that actually didn't have it? Why do you assume the rate of false positive to be in one direction or the other?