A hospital radiology technician, who was addicted to narcotics, infected 45 patients with hepatitis C — one of whom died — before authorities caught up with him, Newsweek reports.

David Kwiatkowski worked his way through 19 hospitals in eight states over the course of 9 years, stealing patient medication and sometimes leaving sick patients with nothing but vials of saline.
He was unreported and unstopped for years by hospitals afraid of the negative attention and staffing agencies that didn't do thorough background checks, Newsweek reports.

In the magazine’s latest issue, Kwiatkowski tells his story for the first time, saying he hopes that spreading the word of what he did will help other hospitals from preventing similar acts from happening.

According to a recent study by the Centers for Disease Control and Prevention, nearly 30,000 people may have been exposed to hepatitis C over the past decade by infected hospital employees using narcotics intended for patients.