(ABCNews)-- A Tulsa-area dentist accused of using rusty equipment and dirty needles is responsible for the country's first known outbreak of hepatitis C among dental patients, health officials said today.
Dr. W. Scott Harrington's practice was shut down in March 2013 after a surprise inspection revealed major lapses in sterility practices. At least 89 of Harrington's patients have since tested positive for hepatitis C.
"This is the first documented report of patient-to-patient transmission of hepatitis C virus associated with a dental setting in the United States," state epidemiologist Dr. Kristy Bradley said in a statement. "While dental procedures are generally safe, this reinforces the importance of adhering to strict infection control procedures in dental settings."
Harrington allegedly re-used needles, a practice that can contaminate drugs with disease-causing pathogens. The dentist of 36 years kept a separate set of tools for patients known to carry an infectious disease, according to a complaint filed by the Oklahoma Board of Dentistry. But the tools had red-brown rust spots, indicating that they were "porous and cannot be properly sterilized."
"The basic things that everyone knows -- follow CDC guidelines, use clean syringes, don't reuse multi-dose vials in multiple patients, don't use rusted equipment -- those are things even non-physicians know," board president Susan Rogers told ABC News in March. "Those are basic things. That part makes it egregious."
More than 7,000 patients from Harrington's Tulsa and Owasso clinics were sent letters in late March outlining the risk of infection and steps to obtain free blood testing. Of 4,202 people tested at state clinics, 89 tested positive for hepatitis C, five for hepatitis B and four for HIV. An unknown number of patients also sought testing through private clinics, according to the state health department.
"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," said Bradley, who in March explained that the investigation into the outbreak was "complex" and involved in-depth interviews to determine the likelihood that an exposure was linked to Harrington's practice.
Genetic testing for HIV is ongoing, according to the state department of health. A final report will be issued when the testing is complete.
The March inspection by the Oklahoma Board of Dentistry was prompted by a patient testing positive for hepatitis C and HIV with no known risk factors. In its report, the board called Harrington a "menace to the public health," describing how he would pour bleach on patients' wounds until they "turned white."
The investigation into Harrington's practice and the infectious disease testing has cost more than $710,000 in federal, state and local funds, according to the state department of health.
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