Cambridge announces three residents test positive for coronavirus; Harvard confirms one case, awaiting results on second

Public health officials in Cambridge said Friday that three of the city’s residents have tested positive for coronavirus, and Harvard University President Larry Bacow announced one person on campus is also a presumptive positive case, and a second person was awaiting test results.

It was not clear if the Cambridge and Harvard cases involved the same people.

One of the Cambridge residents, a person in their 50s, was a confirmed positive case, while the other two, one person in their 30s and one person in their 40s, were presumptive cases, according to the city’s public health department.

People who receive a positive test result from a state laboratory are considered “presumptive positive” pending confirmatory testing from federal authorities.

Cambridge officials said all three cases are connected to the Biogen conference held in Boston in late February that sickened dozens. Biogen is a Cambridge-based biotech firm.

The number of Massachusetts cases of Covid-19, the disease caused by coronavirus, rose to 123 on Friday. More than 80 of those cases were traced to the conference, which was held at Marriott Long Wharf on Feb. 26 and 27 and drew an international roster of executives.

“We are at a pivotal juncture in slowing the spread of Covid-19 in Cambridge and neighboring communities,” said Claude Jacob, the director of the Cambridge Public Health Department, in a statement. “It is time for all of us in Cambridge—local government, businesses, schools, nonprofits, and residents—to take immediate actions to reduce the number of people who may become sick due to the virus.”

In a separate statement, Bacow said that a member of Harvard’s ommunity was a presumptive coronavirus case and that a second member of the school’s community was awaiting test results. Bacow said a third person who had close contact with the person who tested positive is now being tested. Additional close contacts will be tested as needed, he said.

“We will do everything we can to support these individuals through what is undoubtedly a disconcerting and difficult time,” said Bacow.

Cambridge police spokesman Jeremy Warnick said in an e-mail Friday night the city has three total cases to date.

A Harvard spokesman, in responding to a Globe inquiry, provided a link to Bacow’s statement, which did not detail where the one member of the school’s community who was a presumptive case and the two others who await test results lived.