100p cent would be nice but not possible But yep if it was 100p cent Like any vacc.eg measles Then u would not catch it , however like most virus infections they often change their gnome sequence which is why the flue jab is often aimed at 3 strains and is even a different jab between the North and Southern hemisphere
My covid test isseud 48 hours prior to departure .11 hour flight to SIN. 19 hours in transit in SIN and 2.5 hours SIN - BKK.No issues on arrival.Its ALL about departure