HANOVER — Dartmouth College is suspending all in-person classes because of concerns around transmission of the new coronavirus and will hold remote classes, mainly online, until at least May 1, college officials announced Thursday.

“Undergraduate students are asked not to return to live on campus for the time being, with a small set of exceptions who will remain on campus due to medical, visa status, and other reasons,” Dartmouth President Phil Hanlon and Provost Joe Helble said in an email to the Dartmouth community.

“Whether students remain on campus or return home, all undergraduate classes will be conducted virtually and activities will be limited. Students who are currently out of town must not return to campus.”

Dartmouth has 4,400 undergraduates, many of whom are just now leaving Hanover for spring break after final exams for the winter term. Most had been due back on campus March 30 for start of the spring undergraduate term.

Dartmouth’s campus will remain open during those first five weeks of the spring term, the email said, and faculty and staff, including union employees, “will be paid as usual.” Graduate students will also continue to receive their stipends and are not required to leave campus.

A decision as to whether to extend the suspension of in-person classes will be made by April 20, but the email said undergraduates should “plan for the possibility that they will be away from campus for the entire spring term.”

Final exams for the spring term are currently scheduled to run through June 9, with Dartmouth graduation slated for June 14.

Dartmouth had already announced Wednesday evening that Tuck School of Business classes will go online at least for the first couple of weeks of spring term, affecting about 40 MBA classes.

The other seven Ivy League schools — and a number of other colleges and universities — have announced similar policies. Harvard, for instance, this week told students not to return to campus after its spring recess and to “meet academic requirements remotely.” Harvard said it hoped to move all graduate and undergraduate classes to online instruction by March 23.

And the eight Ivy League schools on Wednesday jointly canceled the remainder of their spring sports season.

Dartmouth’s decision aims to mitigate a number of concerns, including that students who may contract the COVID-19 virus elsewhere during spring break could inadvertently bring it back to campus, where it could spread more rapidly in dorms and other close living quarters.

But it also could deliver a sizable blow to the Hanover-area economy, which already slows down during Dartmouth’s long break from Thanksgiving into early January.

The announcement came after the World Health Organization declared the novel coronavirus to be a pandemic and President Donald Trump announced restrictions on travel from Europe, among other major developments.

Dartmouth officials have emphasized that, to date, no known cases of COVID-19 have been found on campus. In the Upper Valley, two Dartmouth-Hitchcock Medical Center employees and a third Grafton County resident have been diagnosed with the potentially fatal disease.

Elsewhere in New Hampshire, Plymouth State University students were on spring break this week, and classes will resume as scheduled Monday. But the university said courses will be available online for any student who chooses not to return for any reason, not just those who are quarantined.

“While we look forward to students returning to campus, we understand that there are some students and families who may not be comfortable doing this,” the university said.

At the University of New Hampshire, classes after next week's spring break will be online for two weeks starting March 23, with on-campus housing available on a restricted bases. Those who travel to certain locations during the break will be required to quarantine off campus for 14 days before returning.

Keene State College also is suspending all face-to-face classes for two weeks starting March 23, after next week’s spring break. The college is also requiring students, staff and faculty to register their domestic and international travel plans with the college. A similar registration requirement is in place at the New Hampshire Technical Institute in Concord, part of the state community college system.

Material from the Associated Press was used in this report.