CMN - 10/6/2021 13:43
Some information to help answer your question, but does not completely answer the question of what is the "best" way to achieve some level of long lasting immunity.
Covid: What’s the best way to top up our immunity?
James Gallagher
Health and science correspondent
https://www.bbc.com/news/health-58270098
It is a pretty well written article IMO...don't disregard the article as "left wing propaganda" because it is from the BBC. Read the article all the way to the end.