Concerned about recent coronavirus outbreaks among prisoners in Massachusetts, the state’s public defenders’ office on Wednesday urged state officials to test all inmates and work to reduce prison populations.

Anthony Benedetti, chief counsel of the state’s Committee for Public Counsel Services, demanded prisoners be tested regularly amidst concerns of a second wave of the virus in the state’s prisons and jails.

In the last several days, 139 prisoners at the Middleton Jail and House of Correction have tested positive for coronavirus. At the Massachusetts Alcohol and Substance Abuse Center in Plymouth, a facility for men civilly committed to addiction treatment that is run by the state Department of Correction, 29 prisoners recently tested positive.

“The pandemic is not over, and it is irresponsible and unconstitutional to take a business-as-usual approach to incarceration,” Benedetti said in a written statement. “Continuing on this course will put prisoners, staff, their families and the community at risk.”

Since the onset of the pandemic, more than 740 prisoners in Massachusetts have tested positive for the virus. Eight state prisoners and two inmates in the county jails have died from complications linked to the disease, records show. But there have been no recorded deaths since July and the number of active cases dropped to almost zero last month, according to data provided by the American Civil Liberties Union of Massachusetts.

State prisons are no longer on lockdown and in late September, the state Department of Correction announced that it would start allowing visits at its facilities.

Elizabeth Matos, executive director of the Boston-based Prisoners' Legal Services, said advocates worry that state and county officials are becoming complacent.

“It’s very hard to control the spread because there's no ability to socially distance,” Matos said. “And we’ve been hearing widespread reports for a while now that masks are not being consistently worn and that precautions have really, really slacked.”

Several state and county officials said Wednesday they weren’t planning on launching universal testing, but do require staff to wear masks within the facilities.

DOC spokesman Jason Dobson said in a statement that the “DOC continues strategic testing department-wide consistent with DPH guidance.’’ The department also says staff are required to wear face coverings.

Carrie Hill, executive director of the Massachusetts Sheriffs’ Association, said staff and prisoners are required to wear masks. She said the Department of Public Health has recommended that county jails only test asymptomatic people when there has been a potential exposure. “Universal testing has not been recommended,’’ she said.

Some recent cases reflect that when prisons test, they find positive cases.

The state Department of Correction said it ordered testing at the Massachusetts Alcohol and Substance Abuse Center last month after learning that someone had tested positive after leaving the facility. Since then, nearly 30 patients have tested positive and were relocated to a separate area of the facility; admissions have been temporarily stopped.

Sheriff Kevin F. Coppinger, head of the Essex County Sheriff’s Department, released a video Monday detailing the county’s decision to test prisoners and staff last weekend at the Middleton jail after several new cases prompted concern. Since then, they have a total of 139 positive cases. The majority are said to be asymptomatic or experiencing mild symptoms.

Coppinger said the department is caring for those who are sick and working to protect those who aren’t. Everybody is required to wear a mask and social distance, he said. “The safety of every single incarcerated person and every single employee is my top priority,’’ he said.

Advocates also worry that prison populations have not dropped enough. The prison and jail population has fallen from nearly 15,000 in early April to a low of 12,623 in June, according to data released to the ACLU by state and county officials as part of a Supreme Judicial Court ruling. But numbers have been heading back up, reaching 13,130 in late September.

Benedetti said there has been an increase of people being held pretrial while not enough are being released. This is despite the Massachusetts Supreme Judicial Court's April ruling that state officials need to work to reduce prison populations to prevent the spread of COVID-19 — particularly among those awaiting trial and not charged with violent offences.

Benedetti said it’s time to push the state to do more. “We will not stand idly by as this virus ravages our clients and rips away their constitutional protections,” he said.