SAN QUENTIN, Calif. — On a sunny Wednesday at San Quentin State Prison, a handful of people gathered just outside the gates to await the release of their family members. A white van arrived, and two elderly men wearing masks and carrying small bags of belongings walked to the waiting group.

Even here, evidence of the coronavirus pandemic was evident. One man hesitated before embracing the woman waiting for him, and he held her hand at a distance for a few minutes before they got into her parked car.

Frank Richardson, who emerged later in the day, embraced his wife and two sons after nearly four years in prison, but he said he’d considered keeping his distance. “I’ve tested negative for a while now, but I’m struggling with it,” he said. “We will definitely have that talk on the way home.”

Thousands of incarcerated people have tested positive for the coronavirus in an outbreak at San Quentin, according to the California Department of Corrections and Rehabilitation, and 19 have died. Like Richardson, about 18 percent of the prison population has been released early to limit the spread. But after having tested positive, those who remain incarcerated have lost their visiting privileges with loved ones, have been limited to showering only once a week and have been placed in solitary confinement, regardless of their behavior, family members told NBC News.

Lisa Zinnamon Noel said Stephen Rhashiyd Zinnamon, her brother, who is soon up for parole at San Quentin, tested positive for the virus in early June and has been in solitary confinement, or “the hole,” for at least a month.

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“He described it basically as a living hell,” she said of conditions at California’s oldest prison during the pandemic. “And no word from the prison system as to when he might be retested or what the protocol is for reintroducing them into the general population. Because you just can’t keep them there indefinitely.”

She said that when he calls, it’s hard to understand him over the shouting in the background, which she takes as an indication of overcrowding and his inability to socially distance from others in that part of the prison. “I believe they only get to shower once a week,” she said. “They don’t get any yard time. He’s not able to work.”

In a statement, the California Department of Corrections and Rehabilitation said that “since the coronavirus pandemic hit our community, the department has worked tirelessly to implement measures to protect staff, the incarcerated population, and the community at large.” While it had to suspend recreational yard time and phone calls, the department wrote, as of July 24 that access had been restored in a limited fashion.

“There are currently 526 incarcerated persons who are actively positive with COVID-19,” the department wrote, calling it a significant drop from earlier numbers, with “over 1,500 persons identified as ‘recovered.'”

San Quentin has also repurposed several areas of its grounds as treatment facilities, including a chapel and a furniture-building shop, and it has installed an air-conditioned outdoor tent with room to treat 164 patients, corrections department spokesperson Dana Simas said. She added that San Quentin is providing personal protective equipment, including cloth masks, to people imprisoned there and offering coronavirus testing every seven days to anyone who has previously tested negative or who has refused a test in the past.

“Those being placed into segregated housing due to COVID-19 are not being moved for punitive reasons,” the department wrote in a statement on its site. “They are moved in order to prevent further spread of the Covid-19 virus in the affected unit.”

An initial lack of screening likely contributed to the outbreak. The corrections department did not test nearly 200 prisoners before transferring them from a men’s institution in Chino to San Quentin and other prisons, the San Francisco Chronicle reported in June.

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Several of the arrivals at San Quentin later tested positive, and as of Wednesday, the department’s official count listed at least 2,168 confirmed past and current cases among people in prison, as well as at least 254 staff members. On Sunday, Johnny Avila Jr. became the 19th man incarcerated at San Quentin to die of the disease. Avila, who was sentenced to death in 1996, was 62 years old.

Avila, like any prisoner, had fundamental rights, even on death row, to health care and due process, said Adnan Khan, who served the final four years of his 16 years behind bars in San Quentin before his release in 2019. Khan is the executive director of Re:Store Justice, a California nonprofit that helps people released from prison fight the stigma of having been incarcerated.

“I was sentenced to 25 to life in prison,” he said. “But I was not sentenced to die of COVID.” Khan said chronic overcrowding and overly long sentences at California’s prisons are to blame for the crisis. “The reason that we have a COVID-in-prison problem is because we have a mass incarceration problem.”

NBC News is not reporting the men’s crimes because they have no bearing on their right to adequate health care.

Richardson said that in his unit, about 80 men sleep in bunks divided by low brick walls and breathe the same air in a single room. He said that he and the people incarcerated with him had been steadfastly wearing masks since April but that mask-wearing by corrections officers had been inconsistent until recently.

“They wear them just on their mouth, not on their nose. Some of them have them just around their neck. I’ve seen them in the yard without them on,” Richardson said. He described trying to persuade one guard to wear a mask. “He goes, ‘Don’t worry about me, dude, worry about yourself.’ And I’m like ‘I am kind of worried about myself.'”

In a June memo, researchers from University of California, Berkeley’s School of Public Health and Amend, a program at the University of California, San Francisco, that seeks to change U.S. prison policy based on European models, predicted a “full-blown local epidemic and health care crisis in the prison and surrounding communities” and offered detailed recommendations to prison officials, including that the incarcerated population be reduced by at least 50 percent to slow the virus’s spread.

The problem is not limited to San Quentin, nor to California facilities.

By July 21, at least 70,717 people in prison in the U.S. had tested positive for the coronavirus, according to research from The Marshall Project, a nonprofit news organization that covers criminal justice, and the disease has killed at least 713. And yet families say they have limited information on their imprisoned relatives.

Jacque Wilson, a public defender in San Francisco, has a brother in federal custody at Terminal Island in Los Angeles and another detained at the Navajo County Jail in Arizona. Wilson’s brother Lance tested positive for COVID-19 at Terminal Island, a federal facility, but the prison has largely cut off contact with his family, Wilson said.

He said he learned of his brother’s condition by letter. And in a video recorded inside the Arizona facility published on Twitter, his brother Neko complains of leaking toilets, no masks and unsafe conditions. “It’s incredibly frustrating,” Wilson said.

Richardson said he worries for the people he is leaving behind at San Quentin. “It’s good to see they’re letting people out. There’s a lot of good people in there that made a mistake,” he said before getting into a car with his family. “I feel sorry for those guys, because they’re in a big incubation box.”