Seoul has one of the largest public transportation systems in the world, so they did an enormous study to see the impact of mandatory wearing of masks + social distancing on public transport during peak hours.

Guess what they found?https://t.co/GfLN0QQYH9

— Barry Ritholtz (@ritholtz) November 16, 2021

Masks work, particularly in crowded and not well-ventilated environs. No surprise because I read the studies almost two years ago now. And now we have even better evidence. Too bad, because I really fucking hate masks. Hate them so much.