There is a good chance this happens more than one would expect (albeit, its still rare).NY man dies shortly after vaccination, allergic reaction not suspected
NEW YORK - A man died shortly after receiving a COVID-19 vaccination at the Javits Center in Manhattan but it was not believed to be due to an allergic reaction, state officials say.
The man, in his 70s, collapsed as he was leaving the vaccination site on Sunday morning.
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Generally, if nothing happens after 15 minutes the vaccine is considered 'not at fault' to future health issues; unless you can prove otherwise.