On these campuses and some others, a rapidly intensifying hunt is underway to find students who are carrying a dangerous pathogen but don’t know it. Mass testing centers are popping up in stadiums and parking lots and under the shade of tents as students line up to fulfill their public health duty. The outcome of the quest could help determine whether residence halls remain open in the fall term and at least some face-to-face teaching survives.
Yet a growing number of universities in recent weeks have learned that these measures are not enough to sustain in-person teaching amid a pandemic that has killed more than 180,000 Americans and sickened many more. Spikes in cases have led schools such as the University of North Carolina at Chapel Hill to retreat to online instruction and empty much of their campus housing.
“You’ve got to add something else,” said Carl T. Bergstrom, a