Although classes have moved to online only, campuses remain open.
The school is the third statewide to discover traces of the virus on its campus, NJ.com reports.
The first case was announced March 12 -- the other two were reported Wednesday night.
The employee had not visited campus in the nearly two weeks after testing positive, and they were not showing symptoms when leaving their office, officials said.
The risk of transmission was considered low at the time, reports say.
The first of the two new cases is an office worker at 855 Valley Road who last visited on March 12. The patient is recovering at home and was not hospitalized, officials said.
The second case announced is a New York City resident, also recovering at home, whose last trip to the school’s campus was last Friday, officials said.
Employees working at the 855 Valley Road Office, as well as another office the patient visited regularly, were notified of potential exposure Wednesday and subsequently self-quarantined to work remotely until March 30.
The school has since been closed to non-essential personnel but is continuing to permit some students to live on campus, reports say
A letter from The Council of New Jersey State College Locals criticized the decision, citing a failure to relay critical information.
“The Union has been provided with no information as to why that institution has not shut down in the same manner as its sister colleges and universities,” the letter said.
“Aside from the obvious health concerns this situation raises, it is symptomatic of a more general failure of some the institutions to share vital information with the Unions.”
Meanwhile, both of the school’s offices were closed for deep cleaning.
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