Michigan health authorities named four hospitals where suspected serial infector David Kwiatkowski worked during the mid-2000s and urged testing for any patients who received injectable narcotics during his employment time frames.

In addition, Michigan health officials said Kwiatkowski tested negative for hepatitis C sometime before June 2005. The negative test allowed them to rule out the potential for Kwiatkowski-related infections at two other hospitals.

Kwiatkowski, a former medical technician at Exeter Hospital, was arrested two weeks ago on federal charges in connection with a hepatitis C outbreak at Exeter Hospital.

He is suspected to have infected at least 30 Exeter Hospital patients with the chronic disease. Authorities claim he injected himself with hospital syringes filled with the powerful painkiller fentanyl, replaced them with another liquid and returned them to be used on unsuspecting patients.

He tested positive for the chronic disease in 2010.

A traveling medical technician, Kwiatkowski worked at as many as 12 hospitals in at least eight states in recent years, bouncing from one job to another to fill staffing shortages.

In addition to New Hampshire, Kwiatkowski worked in Georgia, Kansas, Maryland, New York, Arizona, Pennsylvania and Michigan.

On Monday, Michigan public health authorities named four of the six hospitals where Kwiatkowski, a Michigan native, had worked, and the time frames of his employment.

The four hospitals involved short-term employment. At one — Harper Hospital in Detroit — Kwiatkowski worked at the cardiac catheterization laboratory, the same assignment he had at Exeter Hospital.

The other hospitals are Sinai Grace in Detroit, University of Michigan Health System in Ann Arbor and Oakwood Annapolis in Wayne.

Officials at the University of Michigan Health System would not say why Kwiatkowski left the hospital, AnnArbor.com reported.

Angela Minicuci, spokesman for the Michigan Department of Community Health, said officials are investigating the outbreak in conjunction with the four hospitals.

She said Kwiatkowski was required to be tested at one of the two earlier healthcare facilities where he worked in Michigan. That test, taken sometime before June 2005, was negative for the disease.

She said the state does not require such tests of health care workers, and no more details about the test are available. She said officials will not name the two hospitals where Kwiatkowski had worked before the test took place.

After leaving Michigan, he was fired from hospitals in Pennsylvania and Arizona.

mhayward@unionleader.com