According to one of the Chinese scientists involved, they had isolated a bat virus and were "improving" it when it was accidentally released in that disgusting Wuhan "wet market".
Coincidentally, there have been a number of Chinese students that have been caught trying to smuggle vials of various disease cultures through Customs as they were returning to U.S. colleges.
By the way, China is re-opening their wet markets, which are suspected to be the sources of many previous disease epidemics... .
I still think that the pandemic was supposed to originate in one of our Ivy League colleges and spreed from there - thus making us as hated as China is apparently becoming.
It probably wouldn't have been the Wuhan strain, as that hasn't been "improved" enough and they haven't developed any vaccines yet.
No, it would probably be something that would let them sweep in with a cure, making them the heroes of the world - after the disease effectively crippled their opponents... .