Good questions. I think the event should be suspended and everyone there in quarantine. That’s an extended C if you are keeping score. Test results usually take several days.
Please revise your language, however. It is COVID-19, the disease, or SARS-CoV-2, the virus. Wuhan virus, Chinese virus, and similar terms are not only incorrect, they are harmful.
See https://www.who.int/emergencies/diseases/novel-coronavirus-2019/technical-guidance/naming-the-coronavirus-disease-(covid-2019)-and-the-virus-that-causes-it
Nepo is leading by a full point after 6 rounds, with a sterling score of 4.5/6. He was coughing noticeably in the post-game conference, a great win over Ding with the White pieces, and he was thinking of getting a quick draw because he wasn't feeling well.
Suppose Nepo tests positive for the Wuhan virus on the rest day. What should the FIDE organizers do?
A) Cancel the tournament and start over later with the scores reset to 0 for everybody.
B) Cancel the tournament and start over later with the scores reset to 0 for everybody and Radjabov plays instead of MVL.
C) Suspend the tournament and play later with all scores carrying over from after Round 6.
D) Continue the tournament but without Nepo.
If these were the Candidate Moves under consideration by the Organizers (pun intended), then which move choice do you think they should select?
I would choose Option C. How about you?