Vaccinated people with prior COVID infection had strongest protection during delta, CDC study finds ABC NewsPrior infection, vaccines provide best protection from COVID Yahoo NewsNew data show those who recovered from Covid-19 were less likely than vaccinated to get infected during Delta wave STATADHS report shows unvaccinated at 17.5 times greater risk of COVID hospitalization KTAR.comNatural immunity more potent than vaccines during US Delta wave: study Jakarta PostView Full Coverage on Google News