“It’s not a big mystery why this is happening… lots of concentrated population, with intimate contact with lots of species of animals that are potential reservoirs, and they don’t have great hygiene required. It’s a recipe for spitting out these kinds of viruses,” Dr. Steven Novella recently opined on an episode of the Skeptics’ Guide to the Universe.

South Central China is a noted “mixing vessel” for viruses, Dr. Peter Daszak, President of EcoHealth Alliance, told PBS in 2016. There’s lots of livestock farming, particularly poultry and pigs, with limited sanitation and lax oversight. Farmers often bring their livestock to “wet markets” where they can come into contact with all sorts of exotic animals. The various birds, mammals, and reptiles host viruses that can jump species and rapidly mutate, even potentially infecting humans. Experts are pretty sure this is precisely what happened with the current COVID-19 coronavirus, which is why, on January 30th, China issued a temporary ban on the trade of wild animals.

There are also cultural reasons why China plays host to large outbreaks.