A recent study from Washington State University showed an alarming amount of prison employees—19%, or just under 1 in 5—suffered from diagnosable PTSD. This is a rate equal to veterans of the Iraq and Afghanistan war, and a higher rate of PTSD than police officers.
Prison employees routinely witness violence, suffering, and—one can imagine—existential crises such as wrongful imprisonment that we on the outside can only dimly imagine. The rate of PTSD amongst the general population is around 3.5%, meaning that prison employees were about 6 times more likely to develop it. About 15% of those surveyed experienced bad flashbacks or nightmares related to what they had seen. You can access the study here.
The study took test results from 355 employees from the Washington State Department of Corrections, who were surveyed using the PTSD checklist from the DSM-5 (PCL-5), and the Critical Incident History Questionnaire.
What can be done? Perhaps build less prisons. Between 1990 and 2005 in the U.S., a new prison was built roughly every 10 days or so. That number is dropping, yet prisons are becoming privatised to bring in more cash flow. America has only 5% of the world's population but 25% of the world's prison population. With 2.25 million people in prison in America, with an average cost to taxpayers of $31,000 per year per inmate, it's a sad state of affairs.
If you want some more info (with some jokes), John Oliver did a whole segment on America's prison problem a few years ago.