School officials said after four student-athletes on the campus tested positive Monday, they tested more than 600 members of the community and found another 16 students who also tested positive.
The 20 students are in isolation and their contacts are also quarantining.
"As required by law, we informed the Westchester County Department of Health of these cases," officials said. "Because 18 of our 20 positive cases are students living in Alumni Hall, the county is requiring a 14-day quarantine for all students who live in Alumni Hall. Any Alumni Hall students who have left the residence hall will be required to self-quarantine at home for at least 14 days. Additional testing will be conducted in the upcoming week."
Students who are quarantining on campus are asked to remain in their dorms for two weeks to avoid the risk of exposure to family, friends, and others.
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Meals will be delivered to those students in their dorm rooms and residence hall staff are on hand to support the students.
"While this news is obviously unwelcome, we were prepared for it, and have taken actions to protect our students and the community," school officials said in a statement. "We are proud of the students who responsibly reported their symptoms and got tested, and we're pleased that the systems in place worked to help us confront this outbreak so quickly."
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Officials say they are continuing to disinfect and clean all of their facilities and faculty will work to accommodate the remote learning needs of students.
Additionally, each week, a random sample of 25 percent of those who have been on campus-including students, faculty, and staff will be selected for testing.
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