THE NUMBER of COVID-19 cases at the medium security state prison in Shirley spiked from five just two weeks ago to 142 as of Tuesday, according to the Department of Correction.

There are currently 832 individuals incarcerated at MCI-Shirley medium, according to weekly count data, which means 17 percent of the population has tested positive for the coronavirus.

Case counts have also been rising at other prisons. There are currently 96 prisoners with COVID-19 at MCI-Concord, which has seen a large cluster of ongoing cases for the past month. MCI-Norfolk, which had a large cluster, is now down to 26 cases. There also three at MCI-Shirley minimum, one at NCCI Gardner, one at Pondville Correctional Center, and one at Lemuel Shattuck Hospital Correctional Unit.

Overall, 270 of the 6,700 inmates in the state prison system had the virus as of Tuesday, according to statistics provided by the Department of Correction.

One public defender, Dave Rangaviz, tweeted he’s heard the prisoner case count is much higher at NCCI Gardner — 31 cases instead of just one. “It’s because they only report PCR [molecular] confirmatory tests as positives, not rapid tests,” said Rangaviz in an interview.

A number of staff also have the virus – 42 at MCI-Concord, 21 at MCI-Shirley medium, 23 at the Massachusetts Alcohol and Substance Abuse Center in Plymouth, and 10 at MCI-Norfolk. The remaining prisons and offices have a smaller number of staff cases.

The Department of Correction said it continues to do ongoing testing of symptomatic individuals in all of its facilities, and has conducted 16,000 COVID-19 tests for inmates across all 16 facilities since April. This is contrary to what lawmakers said they were told in a recent call with top state officials, who allegedly said they would conduct constant surveillance testing, including of symptomatic individuals.

“Comprehensive mobile testing is under way department-wide for inmates, patients, and direct custody staff at all facilities. Additionally, day-to-day testing of any symptomatic inmates and patients and their close contacts is also ongoing,” said a spokesman in an emailed statement.

The number of deaths at prison facilities since early last spring remains at eight – five at the Massachusetts Treatment Center and three at MCI-Shirley.

Family and friend visitation at state prisons has been suspended for over a week as prisoners continue to undergo testing and the Department of Correction tries to get the virus spread under control. Staff also recently received their first required round of testing.

Prisoners and their attorneys at Prisoners’ Legal Services are currently suing the Department of Correction to transition some inmates to home confinement. Legislators have said the Baker administration pledged to start the first steps of that process, but the department has not commented on its plans.