A model based on data from correctional facilities has predicted 99% of the nearly 42,000 people in Arizona prisons will become infected with the coronavirus.

As of Wednesday, 35 total inmates have tested positive for COVID-19 in Arizona prisons at four different facilities. Twenty-three of the positive cases are at the Florence state prison.

Only 173 inmates or 0.41% of the total population in Arizona prisons has been tested.

Recently, the Ohio Department of Corrections tested every single inmate in one of their prisons and found that more than 70% were positive for COVID-19.

But most departments of corrections aren’t coming anywhere near that level of testing. Felicity Rose, director of research and policy for criminal justice reform at FWD.US, says the low number of positives are leading to a false sense of security.

“The reality is that a lot of prison systems, including Arizona’s, are not testing nearly enough people,"Rose said. "We know that it’s spreading among staff and that staff are bringing it into and out of the facilities. We know there are people who are asymptomatic and are able to pass it along, but we just don’t know how many. So it’s a ticking time bomb really that people haven’t been accounting for enough in a lot of the models of how this is going to impact the whole system.”

Rose used publicly available data from the Arizona Department of Corrections. She says one important data point is that 90% of inmates in Arizona prisons live in dormitory-style settings instead of individual cells. Rose says the Arizona projections were created by putting the data into a COVID-19 incarceration model.

"It’s based from the 1918 flu pandemic in a prison setting," Rose said of the model. "The novel coronavirus is actually probably even more contagious than that, so it may even go faster. But basically what we see is that each person who is infected is modeled to infect three to four additional people. Whereas in the public setting you see usually every person infects maybe two people. What social distancing is trying to do is to get that number under one so that you’re actually reducing the number. But in prison that’s not possible. So what we’re predicting in Arizona is that within a few weeks of the virus really getting going within the prison system, it will infect almost everybody in the system.”

The implications of the study are grave. Rose says while many inmates will be asymptomatic, the virus will cause mass hospitalizations and deaths. The study is predicting 1,400 inmates in Arizona prisons will need to be hospitalized and more than 350 inmates are projected to die.

Rose says those numbers could be low because the FWD.US report did not factor in the predominantly male prison population. "The coronavirus takes a harder toll on males," Rose said. She said the study also did not take into account the large percentage of incarcerated people with underlying health care conditions.

The Arizona Department of Corrections’ health care provider estimates there are 6,600 people in the prisons who are highly vulnerable to the coronavirus due to their age and poor health.

Rose said the study shows Arizona is not ready for such a huge influx of sick inmates into the system. "The report says at least 1,400 inmates need to be hospitalized," Rose said. "And 1,400 inmates would take up 12% percent of Arizona’s total available hospital beds."

“It’s absolutely very scary what could happen in a lot of rural communities where a lot of prisons are located," Rose said. "There is no way to seal these prisons off. Many people in those communities work inside the prisons. They go back and forth. It could very easily overwhelm a lot of our rural hospitals."

The report projects Arizona prison numbers will spike in a few weeks. Because the numbers are so drastic, Rose said FWD.US is calling for inmates to be released. The Governor’s Office and the Department of Corrections director have shown no indications that they are open to releasing any inmates.

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