There are now 1,011 active cases of COVID-19 at San Quentin State Prison, meaning that almost a third of the entire prison population has become infected in the span of just two weeks.

The San Quentin super-cluster grew overnight from 832 cases to 1,015 cases, according to data from the state Department of Corrections and Rehabilitation (CDCR) — a jump of 22 percent, or 183 cases. It's also a five-fold increase since a week ago, when 219 inmates had tested positive.

We learned as the outbreak began that it was caused by a transfer of 121 inmates from the California Institute for Men at Chino on May 31. San Quentin had not had an inmate test positive until that time, and we learned via an inmate last week that many of those transferred inmates were placed in the upper tiers of a unit known as Badger. With only bars on their cells and poor ventilation in the unit, infected inmates from Chino soon had given the virus to dozens and now over a thousand San Quentin inmates.

As of last Monday, 30 staff members at the prison had also become infected. And the Department of Corrections now says that five of the infected inmates have been released. No cases are yet listed as "resolved," and as of today, the prison has counted its first death, likely to be from COVID-19. 71-year-old Death Row inmate Richard Stitely was found dead in his cell last week after refusing to be tested for the virus, and today Marin County officials announced that he had tested positive, post-mortem.

The San Quentin cluster now represents almost half of all confirmed COVID-19 cases in the California prison system — the total stands at 2,589 as of Monday. The next largest outbreak is at Chino, where there have been 518 cases and 16 deaths.

"We are closely monitoring and quickly responding to positive cases of COVID-19 in state prisons, including at San Quentin," says CDCR Press Secretary Dana Simas in a statement. "Additionally, we are working closely with California Correctional Health Care Services (court-appointed Federal Receiver) as well as public health agencies and stakeholders for the safety and security of our incarcerated population, staff, and communities."

UCSF and UC Berkeley medical experts issued a memo late last week warning the CDCR that the San Quentin outbreak could end up impacting the broader Bay Area as inmates require hospitalization.

Two weeks ago, Marin County Health Officer Dr. Matt Willis discussed how the county was separating out the reporting of San Quentin cases from cases in the community at large. "Otherwise it would mixed," Willis said, "and it would make it difficult to see the signal of transmission within Marin County residents, versus what may be happening in that more sequestered setting that we have very little control over. It's a unique epidemiology there."

Marin County has had 1,166 COVID cases to date, not including the San Quentin outbreak. That is up by 683 cases, or 141 percent since June 1.

Related: Bay Area Coronavirus Information — Update Daily

This post has been updated to record the death of Richard Stitely.