To efficiently block Covid infections and transmission, we need to get high levels of secretory IgA, reflecting mucosal immunity. Important work by @florian_krammer and colleagues; his bottom line below says it all. The case for nasal or oral vaccines https://t.co/Gb2tTk5rDT pic.twitter.com/EjGHjytdWp

— Eric Topol (@EricTopol) September 2, 2022