ER Decontaminated after Mystery Rash affects Postal/Courthouse/Hospital Employees

In addition to an unknown number of hospital employees, 18 people who worked for the post office and courthouse in Pike County, Kentucky broke out in unexplained itching and rash while at work. Offices were evacuated after employees came down with symptoms and subsequently were treated at Williamson Regional Hospital:

Post Office, Courthouse Workers Treated After Mysterious Itching And Rash Breaks Out
The incident occurred at around 10:30 a.m. Several employees who work in the Pike County post office started complaining of intense itching. They work in the same building as the courthouse and employees there felt the same symptoms.

The entire building was evacuated, and 18 people were treated at an area hospital. The Williamson Regional Hospital emergency room was evacuated and decontaminated later in the day after one of the people who work in the courthouse went to the hospital on his own. Soon after, hospital employees complained of similar symptoms. Patients had to be taken to another hospital while crews de-contaminated the ER.

No one apparently knows what caused the skin reaction so far. I'm really disturbed that whatever caused this may have "followed" the employees over to the hospital where hospital employees themselves began to show symptoms, and they felt the need to decontaminate the emergency room!

Zowie!

Kinda sounds like one heck of a kids itching powder prank, or a test run for something worse, doesn't it?

Update: The cause of the mystery skin irritation remains unknown after a series of test turned up no culprits! Despite the fact that testing was unable to identify what caused the health problems, the post office/courthouse has reopened:

Post Office Has Re-opened
The Belfry Post Office and courthouse opened back up Wednesday. Pike County Emergency Management officials say they couldn't find any health threats inside the building. All radiation, biological, and chemical tests inside the building were negative. Lab tests on items from inside the building were also negative for hazardous materials.

I'm really baffled that a skin irritant that quickly affected 18 people, and "travelled" with one person to the hospital, subsequently affecting staff there, could not be found anywhere in the building. No new cases have been reported since the post office/courthouse reopened.