Yeah, I have been in those wet markets in Mainland China, they’re gross. Also the street food vendors in the night markets sell all sorts of gross things like scorpions and centipedes on a stick (scorpions are alive, their stingers have been removed). But frankly we have them here in the U.S. too, we have them here in our local Chinatown and also Filipino communities. I am only assuming that our State Department of Health keeps closer supervision on them than they do in China.
It’s partly cultural, concepts of hygiene are pretty lacking in Mainland China. In distinction, when I am in Korea and Japan, I have no concern buying things from street food vendors, because they have good hygiene cultures. I’ve never gotten sick from any food I’ve bought in Japan or Korea.
Back when borders were relatively firm and international travel was rare (extremely rare in comparison to today) it was less of a threat.
Today, we live in a world where a coronavirus or other pathogen from one bad animal in one wet market could potentially kill tens of millions or more throughout the world. This must be one of the lessons learned from this pandemic.
Different regions in the world have some immunity to such pandemics that might mask it long enough to get a foothold. One example of this is the current pandemic, which has had an outsized impact on ethnic groups the furthest from the center of the pandemic. It is fair to say based on data analysis that Asian cultures and populations had some protections against this pandemic likely from more exposure to similar viruses and lower BMI’s.
Africa has some very really scary ones as well. The same things occur in the plant world. The oak blight in Ohio for example might decimate the oak trees in the mid-west but have little impact on those in the south as a hypothetical.