A former healthcare traveler accused of infecting numerous patients with hepatitis C is expected to plead guilty on Wednesday to 14 criminal counts related to the incident, according to court records. The traveler, David Kwiatkowski, was caught while working at Exeter Hospital in Exeter, N.H.

Kwiatkowski told investigators that he would take a syringe of fentanyl, a controlled substance, and inject himself. He would then replace the fentanyl with saline.

Kwitakowski faces a sentence of between 30 and 40 years under the plea agreement.

The defendant began working as a traveler in November 2007. He took a temporary position at Exeter Hospital in April 2011 and was later hired full-time and worked in the cardiac catheterization lab. In May 2012, the hospital identified several unexplained cases involving hepatitis C. An investigation later found that Kwiatkowski was the source of the infection. Kwiatkowski also told investigators he had swapped out syringes at locations in other states as well.

CNN.com reports 30 people were sickened in multiple states. For the story, click here.