Johns Hopkins University confirms: You can be vaccinated with a PCR test, even without knowing
https://www.cosmicworld.site/johns-hopkins-university-confirms-you-can-be-vaccinated-with-a-pcr-test-even-without-knowing
as seen here
https://www.lewrockwell.com/political-theatre/johns-hopkins-u-confirms-you-can-be-vaccinated-with-a-pcr-swab-test-without-knowing/
(links from as early as last year)