>...rather than nasal/mucosal immunity which prevents infection via the upper respiratory system... Who says? Expansion of tissue-resident CD8+ T cells and CD

>...rather than nasal/mucosal immunity which prevents infection via the upper respiratory system... Who says? Expansion of tissue-resident CD8+ T cells and CD4+ Th17 cells in the nasal mucosa following mRNA COVID-19 vaccination: https://www.biorxiv.org/content/10.1101/2021.05.07.442971v1 https://www.biorxiv.org/content/10.1101/2021.05.07.442971v1 >If there is vaccine escape (e.g. Delta) ... The delta variant does not escape vaccines. They are extremely effective at preventing hospitalization even after antibodies have waned.