By Nick Giovanni

BOSTON (CBS) – The COVID-19 positivity rate in Massachusetts is now up to 3.42 percent as cases start to rise again, even in Boston.

Dr. Paul Sax, the clinical director of the infectious disease clinic at Brigham and Women’s Hospital, said recent wastewater data in Boston is back to mid-February levels.

“After being low in the early part of March it’s been steadily increasing over the last several weeks. It’s impossible to predict how high it’s going to go. The slope of increase is not as steep as it was with omicron,” he told WBZ-TV Tuesday.

This comes as Philadelphia just became the first major city in the country to re-instate an indoor mask mandate for public places. According to Dr. Sax, it’s still a bit early for Boston to consider taking a similar step.

“I’m someone who has been favoring wearing masks indoors from the outset. I would continue to do so in crowded areas especially that that have poor ventilation. I think people who are medically vulnerable should avoid dining indoors in restaurants and avoid going to gyms that are crowded. These are things that we just have to be careful about until we have a better sense of case trajectories because they really are increasing,” he said.

“In the last few weeks, cases in Boston have risen. We are now at a 5.4% community positivity rate, which is above our threshold and we are monitoring that very carefully,” Boston Mayor Michelle Wu said at a news conference Tuesday. “So it’s important that we take steps to protect ourselves and those around us who might be at high risk of severe infection.”

She advised anyone running the marathon to get tested before or after the event and wear a mask, though it’s not required.

When asked about bringing back a mask mandate in the city, the mayor said, “We’re not there yet.”

Nick Giovanni