Well, since they identified it, they can make sure it doesn't spread to other countries and do a better job than they did with COVID-19. If it does get out, I wonder if the WHO will lick China's feet again.
Would China be able to prevent a US citizen from getting out of their country? Somehow I find it hard to imagine a scenario where the Chinese government would be able to say: "Ok, we have this US citizen here that we believe is infected with a new virus. We're going to keep him in lockdown until further notice."