District officials did not reveal whether the case at Hillcrest Elementary School came from a student, staff or faculty member.
The individual had not been in school since Sept. 9, the district website said.
Health investigations and contact tracing determined that the person who tested positive did not pick the virus up at the elementary school nor any other Morris School District building.
Teachers in two Bergen County school districts and nearly a dozen students at a Morris County high school also tested positive.
Teachers and students in the affected class as well as other “close contacts,” meanwhile, are asked to quarantine for two weeks. Students will participate in remote classes during quarantine.
The school building’s exposed areas have also been thoroughly cleaned and sanitized, NorthJersey.com reports.
District health officials say the likeliness for transmission in school remains low considering the school’s sanitizing and social distancing habits.
Families will continue to have the option for all-remote classes until Nov. 13.
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