The hospital worker accused of starting a hepatitis C outbreak at Exeter Hospital is now blamed for cases of the disease discovered in four additional people who were patients at Johns Hopkins Hospital while David Kwiatkowski worked there.

Maryland's Department of Public Health announced that molecular testing done by the Centers for Disease Control and Prevention have found a virus closely related to the infections linked to Kwiatkowski in four new patients, in addition to one who had been previously identified at another hospital.

Seventeen-hundred patients at four health care facilities in Maryland were told that they needed to be tested after Kwiatkowski was linked to the hepatitis C outbreak.

Kwiatkowski faces federal charges in New Hampshire in connection with seven Exeter Hospital patients whose infection with hepatitis C has been linked by authorities to his use of hypodermic needles intended for patients.

Prosecutors say he took prepared narcotic injections, then replaced the drugs in the syringe with a saline solution that would later be injected into a patient through the dirty needle.

An assistant United States Attorney said the seven cases chosen for prosecution were the strongest of the 32 Exeter patients in which investigators have linked infection by hepatitis C to Kwiatkowski.

Kwiatkowski worked at Exeter from Hospital April 2011 until last May. He has been held at the Strafford County House of Correction pending trial. If convicted on all pending charges, he faces a potential sentence of up to 98 years in federal prison.