Three students at the University of Maine have tested positive for the coronavirus ahead of the start of classes and as college campuses around the country are grappling with how to safely return amid the pandemic.

Two of the students live off campus in Orono and the third lives in a fraternity house, University of Maine President Joan Ferrini-Mundy said in an email to the university community Friday.

One of the students participated in the asymptomatic testing program on campus while the others were tested at alternative sites. All three are in isolation and their close contacts are self-quarantining.

The first day of classes across the University of Maine System is Aug. 31 and most residential students will move in next week. Some private colleges, including Colby College and the University of New England, have already started having students move in and will hold their first day of classes next week.

Around the country most colleges and universities are implementing some form of coronavirus testing in an effort to identify and stop the spread among students in close quarters. The New York Times reported Friday it had identified more than 17,000 coronavirus cases linked to college and university campuses in all.

And while colleges have spent the summer preparing for the in-person return of students, many are being forced to change plans because of outbreaks and are struggling to enforce mandates against partying and gathering in large groups.

At Syracuse University in New York, 23 students were issued interim suspensions as the university investigates a large gathering of first-year students that sparked a rebuke from the administration this week as “selfish and reckless.”

The University of North Carolina at Chapel Hill, announced this week that all undergraduate instruction would be moved online after a jump in the positivity rate put more than 500 students in isolation or quarantine.

And a fraternity at Penn State University was placed on interim suspension for a potential violation of COVID-19 rules Thursday as the university’s president also issued a message condemning a large gathering of students without masks or social distancing.

On Friday the University of Maine System posted new student guidance making it clear that hosting a party or function that exceeds Maine’s group-size limitations may be deemed a violation of the student code of conduct, and that students who host or promote prohibited events at any venue, including private residences, may face suspension or dismissal.

Dan Demeritt, a spokesman for the system, said the guidance was not prompted by the three cases reported Friday and the university has no evidence the cases are related to large group gatherings.

The University of Maine System is taking a three-tiered approach to testing students that includes two rounds of asymptomatic COVID-19 testing for all students or staff arriving from out-of-state, residence hall students and special populations upon the return to campuses.

The third tier includes monitoring and additional COVID-19 testing, surveillance and symptom tracking as well as wastewater testing.

Ferrini-Mundy said in her email Friday that the testing program is working as intended.

“We have identified our first case of asymptomatic infection through that program,” she said. “We will be following our comprehensive, science-based plans to maintain vigilance and support all known affected individuals, and to trace and isolate to minimize the spread of the virus and keep our community safe.”

The university system is intending to be transparent with cases and has launched a COVID-19 testing dashboard to be updated daily with data on the number of tests conducted and number of positive results.