WHEN THE BOSTON GLOBE reported Sunday that many colleges and universities throughout the country were reversing their plans to reopen in-person, only Berklee College of Music had taken that step in the Boston area.

Just wait a week.

The Globe reported Wednesday that Smith College in Northampton and Regis College in Weston both scaled back their plans to bring students back to campus in person.

Smith had originally planned to bring back first- and second-year students, and seniors graduating in January. But a Smith official wrote that the worsening pandemic is forcing the college to keep all of its students at home. Regis College said it would allow only upper-class students in laboratory-heavy medical classes to return.

Then on Thursday, UMass Amherst reversed course from its initial plan to allow any student to live on campus, even if they were only taking remote classes. Now, only students taking laboratory, studio, and capstone courses will be allowed to live on campus, MassLive reported. Chancellor Kumble Subbaswamy attributed the reversal to the worsening conditions of the COVID-19 pandemic nationally.

Subbaswamy wrote that given public health data and comparable reopening attempts across the country, he worries about the danger of closing mid-semester and would rather change plans now than risk sending students home during an outbreak.

There are numerous public health reasons that school officials are considering reversing course. Many of these schools attract a significant portion of their student bodies from out of state, and the virus is rampant in much of the US. Massachusetts is also seeing its infection numbers tick upwards. Colleges – with their communal cafeterias, large lectures, and dormitory living – are potential petri dishes for infection to spread. Even with precautions limiting class sizes and common spaces, teenagers and young adults living on their own are unlikely to resist the temptation to throw the occasional dorm room party.

There are also town-gown issues. Amherst’s town manager had expressed concern to UMass Amherst officials that off-campus students partying and traveling around town could pose risks to Amherst residents. Boston city councilor Kenzie Bok recently asked Boston University and Northeastern University, which are both planning to bring students back in person, to only offer remote classes. Both schools have set up elaborate testing protocols and made changes to housing and class sizes, but Bok worried that an influx in out-of-state college students would  endanger local residents, particularly the elderly.

Many schools were already planning to bring back only a portion of their students this fall. Harvard, for example, plans to bring back no more than 40 percent of its undergraduates.

Whether even those limited plans will still be derailed remains to be seen. With students expected to arrive in a matter of weeks, there is little time to change gears. But as the pandemic has already shown time and time again, the best-laid plans can change in a heartbeat.