Only an anecdote and sample of one but hopefully not something that we’ll see more of in the future. Patient had mild symptoms months ago and tested positive then recovered. Had two negative tests then months later tested positive again with more severe symptoms. I believe it has been said that milder cases don’t impart as “durable” antibodies as more moderate/severe cases.
https://www.vox.com/platform/amp/20...d-19-twice-reinfection-antibody-herd-immunity
https://www.vox.com/platform/amp/20...d-19-twice-reinfection-antibody-herd-immunity