AP

In this May 5, 2018, file photo, students attend the University of Toledo commencement ceremony in Toledo, Ohio. Colleges across the U.S. have begun cancelling and curtailing spring graduation events amid fears that the new coronavirus will not have subsided before the stretch of April and May when schools typically invite thousands of visitors to campus to honor graduating seniors.

AP Photo/ Cheryl Senter

In this Sept. 29, 2019 photo, Democratic presidential candidate Sen. Bernie Sanders, I-Vt., pauses while speaking at a campaign event at Dartmouth College in Hanover, N.H. Sanders' campaign said Wednesday the Democratic presidential candidate has had a heart procedure for a blocked artery and that he’s canceling events and appearances "until further notice."

AP Photo/Rogelio V. Solis

A normally student filled campus square at Millsaps College in Jackson, Miss., is deserted in face of the coronavirus, as the liberal arts school, like many others, faces financial and enrollment challenges Friday, April 3, 2020. At present, the school has switched to on-line teaching. Colleges across the nation are scrambling to close deep budget holes and some have been pushed to the brink of collapse after the coronavirus outbreak triggered a series of financial losses.

AP Photo/Ng Han Guan

Travelers with their luggage walk past the Hankou railway station on the eve of its resuming outbound traffic in Wuhan in central China's Hubei province on Tuesday, April 7, 2020. Starting Wednesday, residents of Wuhan will be allowed to once again travel in and out of the sprawling city where the coronavirus pandemic began, ending an 11-week lockdown.

AP Photo/Rajanish Kakade

A doctor engages with people at a slum area during lockdown to control the spread of the new coronavirus in Mumbai, India, Tuesday, April 7, 2020. . The new coronavirus causes mild or moderate symptoms for most people, but for some, especially older adults and people with existing health problems, it can cause more severe illness or death.