Seems Nicholas Christakis is a sociologist ruminating on social impact of something he has no clue about.

Find one from an immunologist.  You might find one being conservative, likely because he/she heard of the "data" coming from China and before he/she considered that their tests suck.

But a reinfection with symptoms would only be with a new virus strain or in an immune-compromised patient.  The first doesn't seem to be an issue (research into that possibility is relatively simple and any scientist in that discipline would love to stake the claim on the notion) and, by definition, wouldn't be a reinfection. The latter possibility would be a case report.