They have a stronger immune system than most westerners, precisely because they live in an environment prone to diseases and bacterias, while westerners live in aseptic environment And it's true for most third world countries, try drinking tap water in LATAM or africa and see how it turns out for you. The locals are used to ti, not you So that's a wrong asumption on your part, for a start When was the last time china closed factories like samsung and foxconn over a mere flu? Yeah... Never, and that's the last fucking thing in the world they need, but they had to That alone should tell you something You aren't paying attention