So two "reinfections" out of 26,000,000 (or 41,000,000 if you prefer Worldometers numbers).
Just flukes of nature. Why write a paper about it? Why draw any conclusions about it regarding vaccines, etc.? And why post it?
RE: And why post it?
Why not? This is for discussion purposes.
The article is from Sept. 4th and the research for it probably occurred some time before that so I don't think they're disputing Worldometer's figures.
But your point remains as stated.
How did the guy with no symptoms know he was reinfected?