TULSA, Okla. (AP) -- A Tulsa-area dentist whose practice was shut down because his equipment was rusty and his employees reused needles was responsible for the nation's first transmission of hepatitis C between patients in a dental office, Oklahoma health officials said Wednesday.
Citing genetic testing performed at the Centers for Disease Control and Prevention, Oklahoma's state epidemiologist said there was at least one instance in which Dr. W. Scott Harrington's practice spread an infectious disease.
"This is the first documented report of patient-to-patient transmission of hepatitis C virus associated with a dental setting in the United States," Dr. Kristy Bradley said. "When this initially began, we didn't necessarily think we would find enough evidence of transmission, but there were enough red flags for us to (investigate)."
Bradley said the probe will not be able to determine exactly how the transmission of the disease occurred but speculated in an interview Wednesday that it could have been the result of contaminated dental instruments or cross-contamination from reused needles or syringes, among other possibilities.
The state said genetic testing of HIV specimens are continuing at the CDC, which confirmed the further tests late Wednesday.
"While our investigation documents the transmission of hepatitis C, we have no reason to believe the hepatitis B cases resulted from exposure in this dental practice," Bradley said.
Industry experts cautioned Wednesday against letting the Harrington case undermine the work of dentists and oral surgeons in the country who practice safely and correctly.
"You're going to get an outlier such as this case," said Dr. John Molinari, a microbiologist and director of infection control for the Dental Advisor, a research publication in Ann Arbor, Mich. "But the overwhelming majority of dentists, assistants and hygienists" do it right.
State health inspectors shut down Harrington's clinic March 28 after finding unsanitary conditions. A 17-count complaint filed by the state called Harrington a "menace to the public health." The complaint said officials found rusty instruments, potentially contaminated drug vials and improper use of a machine designed to sterilize tools at Harrington's two Tulsa-area offices.
Health officials urged tests for 7,000 of Harrington's patients to determine whether they had contracted an infectious disease. Of 4,202 tested at state clinics, 89 tested positive for hepatitis C, five for hepatitis B and four for the virus that causes AIDS. In only one instance was it proven that the virus was contracted at a clinic, health officials said.
"It's been a hard road, but the bottom line is that the state health department and Dr. Bradley saved people's lives," Oklahoma Board of Dentistry Executive Director Susan Rogers said Wednesday.
Harrington had been a dentist for 36 years before voluntarily giving up his license March 20. He faces a January hearing before the state's dental board.
Earlier this month, seven of Harrington's patients filed a class-action lawsuit in Tulsa naming the doctor, his corporation, his medical staff and several pharmaceutical companies as defendants.
Five of the seven plaintiffs said in the lawsuit they had been diagnosed with an infectious disease due to the actions of Harrington and the others. The former patients also said they are at risk of contracting blood-borne pathogens.
"Plaintiffs are informed and believe that they were exposed to contaminated propofol vials and/or equipment not effectively sterilized by autoclave components, at the dental clinics which resulted in plaintiffs contracting infectious diseases," the lawsuit stated.
Harrington's attorney in Tulsa, James Secrest II, did not return a phone message seeking comment on the report Wednesday and an assistant at his practice said he was out of the office.
Secrest issued a statement early in the health scare saying his client was cooperating fully with the probe and that Harrington's record with the state dentistry board was "impeccable."
The public alert began after a patient of Harrington's initially tested positive for HIV in a screening at a third-party provider.
Once infected with hepatitis C, roughly eight in 10 people remain infected for life, according to the CDC. But it can take many years for symptoms to develop, and many of those carrying the virus don't know they're infected.
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