According to the Centers for Disease Control and Prevention, anyone who has been in close contact with an infected person should “stay home (quarantine) since symptoms may appear two to 14 days after exposure to the virus,” and should “stay away from others.”
Dr. Michelson, the bioethicist, said of the former vice president, “I don’t see why it’s different for Mr. Biden, or Mr. Trump, or anybody else,” adding, “I think like he, like every other citizen, should abide by the C.D.C. guidance.”
Dr. Irwin Redlener, an expert in pandemic response at the Earth Institute at Columbia University who briefly served on a public health advisory committee for the Biden campaign, described himself as satisfied that Mr. Biden and Mr. Trump had stood sufficiently far apart on the debate stage and suggested that the Biden team shared that view.