They know this vax protects some people, but it also kills some and makes some others die ... Soon?
So they secretly vaccinated their population in early 2019. (Their citizens are already accustomed to obediently doing whatever government requires.)
At that point they were ready to let the virus out to run through the locals (with minimal impact) and then to the world. In fact they may have only vaxd Wuhan, and planned to lock them down and trap them unless they were headed out to other countries.
Then all they had to do was sit back and control their puppets.
China has been open since the west locked down early 2020. Once the fake videos of people dropping in the streets had done their part to stoke fear, and once the WHO / WEF / CCP gave their cucked country leader minions worldwide their instructions, operation “useless eaters” began. (See Schwab’s Great Reset book for reference) CCP has not mandated vaxes. Many Chinese are staying well away from them as more of them than we think know not to trust their government, especially with their health.