1 Ummah under God
This has nothing to do with vaccination. People in general in the "west" lives in environmental what is much more hygienic than in some other countries, thats why they get sick easier when they travel to different kind of place. Actually many allergies comes because of this reason, not because of vaccination.
It also has to do with vaccination. People in the west are pumped into with all these dead virus that if they were to be hit with a supervirus, they would perish when the those in never vaccinated would have a better chance of surviving. This is experts opinion and those free thinkers who are not too keen on pumping our bodies with viruses in order to be "immune" from them.
Those in east naturally have good health as well because they eat healthy and not the chemically induced, sprayed, washed, etc foods of the west and they also most walk wherever they go and are not couch potatoes who hop in their cars even to go to a grocery store. They just have stronger and healthier bodies because the environment they live in.