This is rather dumb.I doubt he actually has it. Give him a couple weeks and he'll be back to have at least one more debate with Biden after using that time in "quarantine" to go over his strategy with his campaign team. Whether or not you support Trump, you have to admit that first debate was a flop that didn't win over undecided voters. Regroup and redeploy is a logical strategy.
He was tested because his aid Hope Hicks came back positive, after he and FLOTUS were around her during that time.
As for the debates, he didn't flop, he did what he intended and kept Biden from getting good sound bites/lies for the media to reinforce. His poll numbers went up, the Telemundo poll showed Hispanics at least liked his performance, and it forced Biden to take contradictory stances on the GND, refunding the police, and his non-answer about packing the court.