New laboratory research reveals more than one path toward robust immunity from COVID-19. A new study finds that two forms of immunity — breakthrough infections following vaccination or natural infection followed by vaccination — provide roughly equal levels of enhanced immune protection. The research follows an earlier study that described extremely high levels of immune response following breakthrough infections — so-called ‘super immunity.’ That study was the first to use multiple live SARS-CoV-2 variants to measure cross-neutralization of blood serum from breakthrough cases.