BOSTON (CBS) — The number of presumptive coronavirus cases in Massachusetts has risen to 12 Saturday, according to the Massachusetts Department of Public Health website. That number is up from seven on Friday.

There is still only one confirmed case of COVID-19 in the state. This case was a man in his 20s who returned from visiting Wuhan, China on Jan. 28. He is recovering.

The five new cases include four people from Middlesex County: a woman in her 40s, a woman in her 50s, a man in his 40s and another man in his 60s. The fifth case is a man in Berkshire County in his 60s, according to the state health department.

“If you read the science, it says that this Coronavirus is very transmissible. You can get it pretty easy,” said Andy Spencer, of Medfield.

On Friday, Boston Mayor Marty Walsh, Gov. Charlie Baker and Human Services Secretary Marylou Sudders detailed that of the seven presumptive cases identified then, three were in Suffolk County, three were in Norfolk County and one was in Middlesex County. That brings the total number of cases, both presumptive and confirmed, to four in Suffolk County, five in Middlesex County, three in Norfolk County and one in Berkshire County.

“Hand sanitizer is especially, is very important to carry with you, knowing that this coronavirus is around,” said Kiera Martin from the South End.

Five of the seven cases from Friday were related to a Biogen conference at the Marriott Long Wharf in Boston. The state health department said that three of the five cases announced Saturday had a direct connection to the Biogen employee conference, one had recently traveled to northern Italy and the fifth case is still under investigation.

In addition, King Philip Regional High School student in Wrentham is in isolation for 14 days, as a safeguard, after returning from international travel.

The State Public Health Lab’s result is considered “presumptive positive,” and will now be sent to the U.S. Centers for Disease Control and Prevention for confirmation.

The risk of COVID-19 to the general public in Massachusetts remains low at this time, the state health department said.