New Jersey logged its fourth coronavirus case Friday as officials detailed that one of the patients — a medical professional at an unnamed Big Apple medical facility — treated 10 people while sick.

The health care professional, a 32-year-old man, has apartments in Midtown Manhattan and Fort Lee, NJ, Mayor Bill de Blasio said Friday. The mayor did not name the city facility where he works.

The man was symptomatic when he clocked in and saw 10 patients at the hospital — while wearing masks and gloves — on Saturday, Feb. 29, before he went for care himself the next day, according to the mayor.

“None of those 10 patients are symptomatic at this point — and this has obviously been a number of days since then so that’s a very good sign that so much time has passed,” de Blasio said during a news conference announcing latest virus updates.

“We are tracing any other contacts now and we’ll have an update on that tomorrow.”

New Jersey’s latest case, a man in his 50s, tested positive for the virus under the state’s COVID-19 kit, but the case will remain a “presumptive” positive until additional results come back from the Centers for Disease Control and Prevention, Gov. Phil Murphy said in a statement.

The state’s four cases include three men and one woman, with ages ranging from the 30s to 60s. Two of the men are isolated in Bergen County hospitals while another is being treated in a Camden medical facility.

The woman, who is in her 30s, is isolated at home, according to New Jersey officials.