The number of confirmed coronavirus cases climbed by 827 on Monday, bringing the total to 141,474, the Department of Public Health reported Monday.
The death toll from confirmed cases rose by 15 to 9,532.
State officials also reported that 17,654 more people had been tested for coronavirus, bringing the total to more than 2.53 million. The number of administered tests climbed to more than 5.23 million. New antibody tests were completed for 186 people, bringing that total to 124,340.
The seven-day average of positive tests per total tests administered, was at 1.2 percent. The lowest observed figure for that metric — a number watched closely by state officials — is 0.8 percent.
The state also offers on its dashboard a different measure of test positivity: daily positive tests per people tested. That number was 2.9 percent. Some experts have suggested that positive tests per people tested is a better measure of the pandemic.
Meanwhile, the three-day average of hospitalized coronavirus patients dropped slightly from 499 to 494. The lowest that metric has been is 302.
The number of hospitals using surge capacity was zero, and the three-day average of deaths from confirmed cases was 18; the lowest that number has been is nine.
The number of new cases announced Monday was the highest single-day total since late May.
The seven-day average of daily coronavirus cases also climbed to 649 on Monday, the highest it’s been since late May. The average bottomed out at 138 on July 5.
Dr. Marc Lipsitch, a professor of epidemiology and director of the Center for Communicable Disease Dynamics at the Harvard T.H. Chan School of Public Health, said Massachusetts was “certainly in better shape” than many other states.
“That’s because of a very relatively cautious approach to reopening and aggressive efforts to contact trace and otherwise reduce transmission” such as by stepped-up testing in hot spots, he said in a media briefing Monday.
But Lipsitch said, “We are going to have the same challenges as everybody else.”
As the weather gets worse, he said, it will be harder to socialize outdoors and people will be driven indoors. People are also getting weary of pandemic restrictions.
He said, “All of these things are real and understandable . . . It’s just that they will lead to more virus transmission.”
Governor Charlie Baker has acknowledged an increase in cases, but has said the state is prepared to deal with them.
The latest data from the Massachusetts Water Resources Authority, which is looking for traces of the virus in wastewater at the Deer Island treatment plant, also adds to a picture of a state that got the virus under control over the summer but has seen it creeping back upward since.