African nations today, June 23rd 2022, low COVID vaccination rates and look at their infection/cases for OMICRON etc.; remember, these nations have lots of background natural immunity

And 'trained' natural 'innate' immunity, that is, innate antibodies & natural killer cells (NK cells) of the innate immune defense that are potent & by remaining 'unvaccinated', innate is 'trained' up

See vaccine rates in some African nations relative to western high vax high COVID infection nations