evidence: Upon vaccination or infection with COVID-19, your body produces two types of protective immune responses. The first type involves B cells, which produce antibodies. [...] Researchers have also found that the protective immunity acquired from the combination of a COVID-19 infection followed by vaccination – called hybrid immunity – is very potent and remains effective for more than a year after infection with COVID-19. [...] Such studies show how important it is for even people who have been previously infected with COVID-19 to get vaccinated to ensure the most robust protection against COVID-19.