Advocate Aurora Health said the employee removed vials of Moderna's vaccine from a pharmacy refrigerator at Aurora Medical Center in Grafton, Wisconsin. That caused most of the doses to expire.
The now-former employee of the hospital was arrested for tampering with and causing the destruction of doses of the vaccine, the Grafton Police Department announced.
The employee worked in the pharmacy at the hospital. He was described as a pharmacist but not identified by name.
The investigation into what happened revealed that the person "removed the vials from the refrigerated storage knowing they would not be usable," police said in a statement.
The expired doses were still administered to patients but health officials believe there are no health concerns related to the spoiled doses, Advocate Aurora Health Care Chief Medical Group Officer Jeff Bahr told reporters in a call.
The value of the expired doses was estimated to be between $8,000 and $11,000.
The pharmacist was booked on charges of first-degree recklessly endangering safety, adulterating a prescription drug, and criminal damage to property, all felonies. Police were assisted by the FBI. The arrest appeared to be the first of its kind, coming weeks after the first COVID-19 vaccine received emergency use authorization.
Officials initially thought what happened was a mistake.
"Over the subsequent days, as we continued our internal review, we became increasingly suspicious of the behavior of the individual in question," Bahr told reporters. "The individual was suspended and after multiple interviews over the course of the week, admitted yesterday to intentionally removing the vaccine from refrigeration."
He said that there is no evidence the pharmacist otherwise tampered with the doses, or tampered with other doses. He also said the facility has secure protocols.
“It's become clear that this was a situation involving a bad actor, as opposed to a bad process,” said Dr. Jeff Bahr. “We’ve certainly used this to have additional dialogue and ensuring learning around our processes.”
In a statement, Advocate said, "we continue to believe that vaccination is our way out of the pandemic."
"We are disappointed that this individual’s actions will result in a delay of more than 500 people receiving their vaccine," it added.
The Wisconsin Department of Health Services (DHS) told news outlets in a statement that it requires any wasted vaccine to be reported, investigated, and addressed through a written plan of improvement.
"Immediately upon notification, DHS followed up with Aurora and has worked closely with them as they have investigated the situation, reviewed their processes and implemented improvements," Wisconsin DHS Secretary Andrea Palm said. "We will continue to work with our healthcare partners to get as many shots in arms as quickly and safely as possible."