Just look at the prior chinese coronavirus-related studies, they did antibody tests in villages near bat caves for SARS-like coronaviruses, some of villagers had antibodies in 2015 despite no reported SARS infections ever near the area.
Simplest conclusion:
Zoonotic diseases sometimes jump from bats to humans in Chinese rural areas. The case clusters stay inside the isolated communities and stop naturally due to low population and lack of super-spreader events that can kickstart an epidemic.
In 2019 it happened again, but this time a villager who was infected visited Wuhan => pandemic
Just look at the prior chinese coronavirus-related studies, they did antibody tests in villages near bat caves for SARS-like coronaviruses, some of villagers had antibodies in 2015 despite no reported SARS infections ever near the area.
Simplest conclusion: Zoonotic diseases sometimes jump from bats to humans in Chinese rural areas. The case clusters stay inside the isolated communities and stop naturally due to low population and lack of super-spreader events that can kickstart an epidemic.
In 2019 it happened again, but this time a villager who was infected visited Wuhan => pandemic