(CN) - California is spending more than $5 million to screen tens of thousands of inmates for valley fever to determine who can be sent to two Central Valley prisons without fear of contracting the disease.
Valley fever - coccidioidomycosis - is caused by a fungus that grows naturally in the soil in California's Central Valley and in other dry areas of the country, including Arizona.
Although most people who get valley fever get better on their own in a matter of weeks or months, certain groups of people are at higher risk for developing a more severe form of the infection and need antifungal treatment, according to the Centers for Disease Control and Prevention.
Those particularly at risk include African Americans, Filipinos, people older than 60, people with weakened immune systems, and diabetics.
Since 2006, 49 inmates in California have died due to valley fever as the primary, secondary or tertiary cause, according to statistics provided by the federal court-appointed receiver who controls prison medical care.
More than 2,600 cases of valley fever in the California Department of Corrections and Rehabilitation were reported from 2008 through 2014, although 2014 had by far the least amount at 38, according to the statistics.
Dozens of lawsuits have been filed by current and former inmates who contracted valley fever while serving time in Avenal State Prison or Pleasant Valley State Prison, both in the Central Valley.
In 2013, a federal judge ordered the state to move nearly 2,600 high-risk inmates out of Avenal and Pleasant Valley state prisons to deal with the valley fever problem.
Two weeks later, a federal class action claimed that California had done nothing to prevent high-risk prisoners - including African Americans, people 55 and older, and those who are immune-compromised - from contracting the disease.
That lawsuit accused the Department of Corrections and Rehabilitation of being aware since at least 2006 that valley fever attacks prison inmates within these subclasses and failing to take adequate steps to protect them from the disease.
Another federal lawsuit filed in July 2014 on behalf of 58 current and former inmates who contracted valley fever accused the state of knowing that the disease was being spread throughout the two Central Valley prisons.
That month, the CDC recommended that the state use skin tests to identify inmates who have been exposed to valley fever. People who have had the illness are largely immune to getting it again, so these inmates could be safely housed at the two prisons.
The receiver had already "implemented medical restrictions barring certain individuals from the two prisons," said information officer Elizabeth Gransee, but they were advised by experts at the CDC that the skin test is "the best public health intervention available."
On Monday, approximately 90,000 of the more than 134,000 state inmates were screened for valley fever at a cost of $60 per skin test. The cost of $5.4 million came out of the medical budget for California's inmate health care, Gransee said.
Results of the tests are expected to be read 44 to 52 hours after the administration.
Those who receive a positive test result are at a much lower risk of getting valley fever and will not have a medical restriction from being housed at Avenal or Pleasant Valley prisons, even if they are African American, Filipino or have diabetes.
Inmates who receive negative test results are considered to be at a higher risk of getting valley fever and will not be housed at the two Central Valley prisons, Gransee said.
The test was voluntary, but women, inmates on condemned row, and those with weakened immune systems or cardiopulmonary disease were not tested.
"This is a one-time screen for all inmates; however, it will eventually be part of the receiving process for new inmates," Gransee said.
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