"You don't necessarily have symptoms in the beginning," said Maria Said, an epidemiologist for the state. "But because of the potential treatment options, something can be done now if a patient tests positive."

The Kwiatkowski case spotlights the use of contract workers in the medical field and how they are regulated.

Kwiatkowski was licensed by the Maryland Board of Physicians as a radiographer, but his license has expired. That board also is investigating whether he violated any regulations, Phillips said.

Generally, contract workers in Maryland have to be licensed like any other medical profession, but they are employed by a staffing firm. A contract nurse would be licensed by the Board of Nursing.

Hospitals use contract workers for a variety of reasons, including filling in for staffers on vacation or unexpected departures, according to The Maryland Hospital Association.

The association said contract workers are common in a number of professions and that their use doesn't put patients in danger. What happened with Kwiatkowski is not common, said Jim Reiter, a spokesman.

"There are the same risks as if with any other human being," Reiter said. "It's just a very unfortunate situation that the guy took advantage of his position."

Hospital officials said they do have safeguards for contract workers.

The VA health care system requires criminal background checks, proof of licensure, registration or certification, and references, spokeswoman Rosalia Scalia said. Contractors also have to obtain certification through the American Registry of Radiologic Technologists.

Hopkins officials said procedures for hiring temporary workers are the same as for regular employees. They require drug testing and background criminal investigations. A Hopkins spokesman said that ultimately the staffing agencies are responsible for ensuring their contract workers are properly screened and credentialed.

Reiter said contract workers are needed as much as full-time employees for patient care.

"You're making sure that no matter what is going on with personnel — whether it is vacation, illness or the economy — you're still taking care of patients the right way," he said.

andrea.walker@baltsun.com

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