evidence: "Fully vaccinated," at least in the context of COVID-19, means you have received all the vaccine doses recommended for someone in your demographic. [...] - Pfizer (mRNA vaccine) [...] COVID-19 vaccinations restrict how much the SARS-CoV-2 virus can replicate in your body. If your body has less virus in it, then you’re less likely to pass the virus on to co-workers, friends, or family.