Good points. We laughed at those "news" from China, though that was a blip against a hurricane of contagion escalation for anybody following regular news stories. USA gov has own Intelligence reports that would be even ahead of the news as well.

https://duckduckgo.com/?q=no+clear+evidence+who

There was a huge debacle at the time with Facebook CEO visiting different countries' authorities and the Cambridge A. scandal:

https://duckduckgo.com/?q=social+media+combat+fake+news+cong...

https://duckduckgo.com/?q=social+media+combat+fake+news

Though active admin moderation on social media, forums and even news sites has a long history before that as well.