A traveling hospital technician accused of causing a hepatitis C outbreak in New Hampshire previously worked at Houston Medical Center in Warner Robins, a hospital official said Friday.

David Kwiatkowski worked as a contract employee at the Cardiac Cath Lab at Houston Medical Center from October 2010-March 2011, according to a statement from Houston Healthcare Chief Executive Officer Cary Martin.

The hospital is working to identify patients who may need to be contacted for testing of hepatitis C, a blood-borne viral infection that can cause liver disease and chronic health issues. Once identified, patients will receive a certified letter. Those letters are expected to go out within two weeks, according to the statement.

“The health of our patients, as well as our employees, is of the utmost concern to us, and we are taking a proactive approach to ensure the safety of our employees and those in our community,” Martin said in his statement.

Kwiatkowski, who grew up in Michigan, worked as a “traveler” sent by staffing agencies to hospitals around the country, usually for temporary jobs. In announcing federal drug charges Thursday, U.S. Attorney John Kacavas called him a “serial infector” who has worked in at least six states, also including Maryland and Michigan, since 2007. Authorities have not publicly identified the others.

Kwiatkowski, who worked at the cardiac lab at Exeter Hospital in New Hampshire from April 2011 until this past May, is accused of stealing anesthetic drugs from the lab, injecting himself and contaminating syringes that were later used on patients, 30 of whom have been diagnosed with the same strain of hepatitis C Kwiatkowski carries.

Kwiatkowski did not have access to the medication system at Houston Medical Center, according to the hospital’s statement.

Though he told investigators he was diagnosed in May, authorities said there is evidence that he has had the disease since at least June 2010.

According to court documents, Kwiatkowski told investigators he did not steal drugs, is “not a shooter,” and is scared of needles. He also said he was allergic to fentanyl, the powerful anesthetic he’s accused of stealing, though medical records indicate he was given the drug during a medical procedure in 2011.

“I did not take any drugs or do any drugs ... and I’m gonna stick to that,” he told investigators. When he was told that a syringe bearing a fentanyl label was found in a bag in his vehicle, he said it was not his and suggested that it had been planted by a co-worker.

Kwiatkowski also said he “lied to a lot of people” and “fabricated my life,” saying two of the biggest lies he had told were claiming he played baseball at the University of Michigan and that his fiancée had died.

Former co-workers in other states told investigators that Kwiatkowski was known for telling false stories, including saying that he had cancer. According to the affidavit, he was fired for falsifying his timesheets at one hospital, was accused of stealing fentanyl from a hospital operating room in 2008 and aroused significant suspicion in Exeter.

One co-worker said he recalled seeing a red-faced, red-eyed Kwiatkowski with white foam around his mouth. Others said he was at times shaky, sweaty and looked like he was “on something.” When a worker complained, Kwiatkowski told a supervisor he had been up since 3 a.m. crying over his aunt’s recent death; his parents later told investigators no relatives had died in the last several years. They also said that while their son took prescription medication and had alcohol and anger problems, he did not use illegal drugs.

Officials at both Exeter Hospital and The Johns Hopkins Hospital said Kwiatkowski underwent drug testing and a criminal background check before being hired.

In a statement Friday, Exeter Hospital said that while employees raised concerns about Kwiatkowski’s appearance, none suspected him of diverting medication. In each case, Kwiatkowski provided plausible explanations related to either personal medical issues or family crises, the hospital said.

“David had stories for everything that pulled at your heart strings and we had no reason to disbelieve him,” said Dr. Thomas Wharton, who oversees the cardiac catheterization lab. He said he now views Kwiatkowski as “the ultimate con artist and an extremely good cardiac technologist who pulled the wool over everyone’s eyes.”

The hospital said it performed additional background checks on Kwiatkowski when he was hired into a full-time position in October. Kwiatkowski held the required certification for the job and was given good references from his previous two employers, including one who had said “David has been invaluable in helping us get our lab up and running.”

Authorities said Kwiatkowski was not authorized to handle medication at Exeter Hospital but they believe he may have switched syringes that were filled by others and set down with syringes he had used and refilled with another liquid, possibly saline. Colleagues told investigators that Kwiatkowski often came in the lab on his days off or attended procedures he wasn’t assigned to, and would bring nurses the lead aprons they wear to protect against radiation exposure.

When asked how the patients had contracted hepatitis C, he told police, “You know, I’m more concerned about myself, my own well-being.”

“I’ve learned here to just worry about myself,” he said. “And that’s all I really care about now.”

Telegraph writer Jennifer Burk contributed to this report.