(Reuters) - A former lab technician faces charges in connection with a hepatitis C outbreak that reportedly infected dozens of patients at a New Hampshire hospital, authorities said.

David Michael Kwiatkowski, 32, is charged with obtaining controlled substances by fraud and tampering with a consumer product, U.S. Attorney John P. Kacavas said this week.

The outbreak at the Exeter Hospital Cardiac Catheterization Unit is believed to have infected some 30 people with the disease, considered the most serious of hepatitis strains, authorities said. Hepatitis C can lead to liver cancer and cirrhosis, and kills more people each year than HIV, according to the Centers for Disease Control and Prevention.

"The evidence gathered to date points irrefutably to Kwiatkowski as the source of the hepatitis C outbreak at Exeter Hospital," Kacavas said. "With his arrest, we have eliminated the menace this 'serial infector' posed to public health and safety."

Kwiatkowski, who worked in the lab until the investigation launched in May, has hepatitis C and is accused of stealing syringes of the powerful pain medication Fentanyl intended for patients. Authorities say he would then inject himself with the drug, then replace it in the tainted syringe with saline solution, which would then be injected into the patient, Kacavas said.

The investigation included testing some 1,100 patients from as far back as October 2010 before Kwiatkowski was identified as a suspect.

"It is deeply disturbing that the alleged callous acts of one individual can have such an impact on so many innocent lives. As a result of his alleged actions, people in our community, who in many cases are the friends and neighbors of the 2,300 people who work here, now face the challenge of a potentially chronic disease," said Kevin Callahan, president and CEO of Exeter Hospital.

Kwiatkowski worked at the hospital in Exeter, New Hampshire, since April 2011 and had been diagnosed with hepatitis C for a year before that, according to a statement by the U.S. Attorney's Office in New Hampshire.

Originally from Michigan, Kwiatkowski worked as a traveling contract medical technician in six other states, which has prompted CDC officials and the U.S. Attorney's office to check into potential public health threats in those states.

Kwiatkowski was arrested on Thursday at a hospital in Massachusetts, where he was being treated for an undisclosed illness. He was expected to be taken into federal custody in New Hampshire upon his discharge from the hospital, authorities said.

The tampering charge carries a 20-year prison sentence, and the controlled substance charge carries up to four years.

Hepatitis C is an infectious liver ailment that afflicts more than 4 million Americans. Up to 85 percent will develop chronic infection. Of those, 75 percent will get chronic liver disease, according to the National Institutes of Health.