More than 1,900 new people in Massachusetts were confirmed to have Covid-19 over the three-day holiday weekend as single-day positivity rates remained above 3 percent, continuing a trend that began in late September.

In Boston, Mayor Walsh said that Dorchester’s zip codes 02121 and 02125 still have the highest positivity rate, although the rate citywide has remained fairly stable at roughly 4.1 percent for two weeks.

The state’s Department of Public Health reported 587 new cases of the coronavirus on Saturday, 570 additional cases on Sunday and 765 fresh cases on Monday, though the agency said Monday’s total included “data from a national laboratory that had a delay in reporting.”

Along with the 1,922 new cases, DPH reported 39 recent Covid-19 deaths since Friday, bringing the death toll to 9,617 people. Since Feb. 1, 136,933 people in Massachusetts have become infected with the virus.

Although the DPH said on Monday that the seven-day average of the positive test rate of all tests conducted remained at 1.1 percent, the agency also reported that 4.2 percent of people tested for the first time Friday were found to be positive for Covid-19, 3.4 percent of people first tested Saturday had the virus, and 3.2 percent of people first tested Sunday were confirmed to have the coronavirus.

The single-day positivity percentage has been above 3 percent since late September, according to DPH.

As of midday Monday, there were 501 people with Covid-19 hospitalized in Massachusetts. That’s down by 30 patients from midday Saturday, but DPH said the three-day average number of hospitalized patients is up 70 percent from the low of about 300 patients in late August.

Also as of midday Monday, 82 people were being treated in an intensive care unit including 32 patients on ventilators.

Dr. David Rosman, president of the Massachusetts Medical Society, took to Twitter each evening this weekend to call attention to trend lines that he said “are still pointing up” and to encourage people to remain vigilant about social distancing and mask-wearing.

Gov. Baker on Tuesday outlined progress the state has made over the past several months and to prepare for a fall uptick in virus activity.

“Over the past few weeks we started to see an increase in the number of Covid cases here and across the country and in many other countries,” Baker said at a State House press conference. “For months, public health experts have forecasted this increase.”

Massachusetts has built a “massive infrastructure to respond to this pandemic,” Baker said, leaving the state “in a strong position to be prepared for what comes next.” Baker added that the state will be able to rapidly expand hospital capacity if necessary, and that there are sufficient personal protective equipment supplies to meet the needs of health care and human service providers.

The preparations, Baker said, “are of little use without the people of Massachusetts continuing to do their part.”

He urged continued vigilance against the virus, “especially as we all move from our backyards to our living rooms and our family rooms” as the weather gets colder. “Household spread. Intergenerational spread. Expect to hear these terms a lot this fall,” Baker said. “We all have a role to play here, and it doesn’t end when we come home from work or the supermarket.”  

Dorchester Reporter staff contributed to this report.