Just saw reporting that one of the goals for the Biden-Xi meeting today is "Being able to pick up the phone and talk to one another if there’s a crisis. Being able to make sure our militaries still have contact with one another." 

I had a Forum post about this earlier this year (with my favorite title) Call Me, Maybe? Hotlines and Global Catastrophic Risks with a section on U.S.-China crisis comms, in case it's of interest:

"For example, after the establishment of an initial presidential-level communications link in 1997, Chinese leaders did not respond to repeated U.S. contact attempts during the 2001 Hainan Island incident. In this incident, Chinese fighter jets got too close to a U.S. spy plane conducting routine operations, and the U.S. plane had to make an emergency landing on Hainan Island. The U.S. plane contained highly classified technology, and the crew destroyed as much of it as they could (allegedly in part by pouring coffee on the equipment) before being captured and interrogated. Throughout the incident, the U.S. attempted to reach Chinese leadership via the hotline, but were unsuccessful, leading U.S. Deputy Secretary of State Richard Armitage to remark that “it seems to be the case that when very, very difficult issues arise, it is sometimes hard to get the Chinese to answer the phone.”

An interesting quote relevant to bio attention hazards from an old CNAS report on Aum Shinrikyo: 

"This unbroken string of failures with botulinum and anthrax eventually convinced the group that making biological weapons was more difficult than Endo [Seiichi Endo, who ran the BW program] was acknowledging. Asahara [Shoko Asahara, the founder/leader of the group] speculated that American comments on the risk of biological weapons were intended to delude would-be terrorists into pursuing this path."

Footnote source in the report: "Interview with Fumihiro Joyu (21 April 2008)."