Major American universities -- including Harvard, Princeton and Columbia -- have been forced to cancel classes because of the coronavirus and move lessons online, affecting tens of thousands of students.
The US government has refrained from imposing an official ban so the often privately run institutions are each grappling with how best to deal with the fast-moving outbreak.
Ahead of the start of spring break at the end of this week, Harvard on Tuesday announced it would transition to having all classes online by Monday 23 March.
The university, located in Cambridge, Massachusets, asked its 36,000 graduate and undergraduate students not to return