@Neverdul .
Thanks for the full explanation.
It just seems like China has more than any other country.
Conditions in other countries in that part of the world are similar to China.
The 1918 flu originated in China.
@ bigheadfred
No one knows exactly from where the 1918 influenza pandemic originated but there are many theories.
One was that it started in Haskell County, Kansas and nearby Fort Riley. Some contemporary reports say was that there was a mass burning of garbage including pig and chick carcasses (not just leftover cooked meat but also dead animals) but weather conditions caused the acrid smoke to stay in the air for hours if not days and it was very soon after that many soldiers, over 100 started reporting to the infirmary with 48 young and seemingly healthy men dying that same March. But many also shipped out around that same time to Europe and then back again to the US where soon cities like Boston and Philadelphia, cities with ports and naval yards starting seeing many people die.
But while that is thought to be the 1st wave and the place where the disease was likely first identified as influenza, another theory places it as originating in China and spread via some 96,000 Chinese laborers who were shipped to the west coast of Canada and across to the east coast to be shipped to England and France to relieve soldiers from menial labor behind the trenches.
https://www.nationalgeographic.com/news/2014/1/140123-spanish-flu-1918-china-origins-pandemic-science-health/As to why so many influenza and other viruses originate from China, it probably has to do a lot with their love of poultry, both domestic and wild and other wild animals, the “wet†markets as they call the live animal markets where even basic sanitation protocols are pretty much non-existent, combined with very densely populated urban areas and much international travel.