In a back-to-school season upended by a global pandemic, second-year college student Seth Mabry is ready to make a boatload of sacrifices to avoid another campus closure.

"I'm just gonna adhere to all the rules and be above reproach," the 19-year-old New York University (NYU) student of educational theater said.

He's not the only one: Caution is the rule to keep this Manhattan campus -- which closed during the early days of the pandemic in the spring -- running, according to a dozen students there interviewed by AFP.

Carolyn Erickson had dreamed of a freshman year rich with social engagements and exciting discoveries about her new city.

But the young woman originally from Fairfax, Virginia said she'll avoid parties and in-person group activities, at least "until there are vaccines."

While waiting for a required COVID-19 test, the student of environmental studies said it reshapes the college experience, but "it's a necessary change."

Many large American universities, NYU included, have kept only a few in-person courses -- if any -- this semester.

Across the country, campus closures have multiplied in recent days: another university in New York, Columbia, announced last week it would cancel all in-person teaching for the fall semester.

The decision followed a similar move from Michigan State and Indiana's Notre Dame, along with the University of North Carolina-Chapel Hill that canceled in-person learning one week after it opened.

Outbreaks linked to gatherings of unmasked students are apparently to blame.

"About 150 colleges and university have already made a full reversal in the past few weeks from primarily in-person instruction to primarily online instruction," said Chris Marsicano, who is studying higher education's response to the pandemic at Davidson College in North Carolina. 

NYU students aren't required to physically be in class, with the option to attend via Zoom video chat.

Less than a quarter of some 5,000 higher education institutions plan to teach completely or partially in person, according to the journal Chronicle of Higher Education.

The pandemic wrought devastation in New York, with more than 23,000 deaths linked to coronavirus.

The infection rate has come under control for the moment, at less than one percent of those tested -- but fear of a second wave remains omnipresent.

NYU has upped its precautions: students must present a negative swab test before attending classes or entering non-residential buildings.

Masks are obligatory in campus buildings, in-person classes are limited, and students are moving into dorms on staggered days. Libraries and gyms remain closed.

"The University is prepared to penalize those who flout the rules," said university president Andrew Hamilton in a message Wednesday, reminding students and faculty that "our collective success or failure will hinge on individual conduct."

- 'Shining example'? -

Peggy Morton, an NYU professor of social work, is among the instructors giving some courses in person, even though the university gave permission to conduct all teaching online. 

"I'm apprehensive like everyone else is about the whole situation, but I feel NYU is doing everything they can," she said, hoping the university can offer a "shining example" on how to re-open while also containing the virus.

The debate over how and whether to physically open campuses has been spirited, and the decisions of certain universities have been swept into the COVID-related political polarization leading into November's election.

Donald Trump has pushed opening all in-person classes. In some Republican-led states, Marsicano said institutions are tending to follow his wishes.

In most Democratic-led states, it's the opposite, he said.

"Universities in red states are feeling political pressure to adopt in-person instructional strategies," according to Marsicano.

The debate is even more heated for K-12 schooling, with the decision whether or not to send children back to school directly impacting parents' ability to work.

In most large American cities, school administrations have opted towards virtual schooling for at least several months.

New York City is planning to resume in-person schooling a few days a week to allow for social distancing, and students are allowed to remain completely remote.

But teachers' unions are threatening to strike if the city's 1.1 million schoolchildren aren't tested before day one -- September 10.