In this April 16, 2020, file photo, a medical worker places a swab in a vial while testing the homeless for COVID-19 through the Miami-Dade County Homeless Trust, during the new coronavirus pandemic, in Miami. Credit: Lynne Sladky | AP

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Two more prisoners have tested positive for COVID-19, the Maine Department of Corrections said Saturday.

The men, inmates at the Maine Correctional Center in Windham, are the third and fourth prisoners in the state to be diagnosed after the facility began campus-wide testing last week after the first positive case was confirmed.

[Our COVID-19 tracker contains the most recent information on Maine cases by county]

So far, 744 test samples have been collected from staff, inmates and contracted vendors. All 283 staff tests were negative for COVID-19, according to the department, with 457 tests from inmates also negative.

One of the men whose positive test was confirmed Saturday is in his 40s, and has been in state custody since May 2016. The other is in his 60s, and has been in custody for 22 years. Neither man has needed to be hospitalized, and both have been moved to an isolation unit, which is standard practice for the Maine Department of Corrections, according to the press release.

[As Maine prisons record 1st case of coronavirus, ‘we need to find it and shut it off now’]

The department is continuing to follow protocols that included contact tracing and restricted movement within the Maine Correctional Center in response to the positive tests, it said.

Nationally, jails and prisons are particularly vulnerable to becoming virus hotspots because of inmates’ close living quarters and their limited access to good hygiene and medical care. The country’s four largest outbreaks, each of more than 1,100 cases, have appeared in correctional facilities, according to the New York Times. In Maine, about half of the prison population are at high risk of complications from the virus because of their age and other health conditions.

Since the virus officially arrived in Maine in mid-March, Maine corrections officials have taken preventative measures that include shutting down outside visits, ramping up cleaning measures, not allowing staff to work at multiple facilities and requiring that they wear protective equipment while on the job. The state has also taken steps to reduce its jail and prison populations.

Watch: Testing at Maine correctional centers

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