The problem at a colposcopy clinic at the Miramichi Regional Hospital began in May 1999 and was detected on May 24 of this year, the province's Horizon Health Network said Wednesday.
"I on behalf of everyone at Horizon apologize for this error and the resulting apprehension this may cause our patients," said John McGarry, the CEO of the Horizon Health Network.
"While I firmly believe that disclosing this information is the right thing to do, I cannot underscore strongly enough that the risk of infection to any of our patients is extremely low."
McGarry said the problem began when the clinic started reusing biopsy forceps without sterilizing them in order to handle a growing patient load. While all of the biopsy forceps were sterilized at the end of every day, during the day some forceps were only cleaned and disinfected before being reused, he said.
"If there were eight patients in the day, chances are the first five patients received sterilized instruments from the night before, but the next three would have had reprocessed instruments that occurred during the day," McGarry told a news conference in Miramichi.
McGarry said it took three months to notify the public about the problem because the health authority had to first ensure that proper sterilization procedures were in place at other hospitals in the province as well as determine the risk of infection.
"We wanted to check into what is the risk, what is the advice from the experts, what is the situation across the country regarding disclosure, because we understand it causes a lot of apprehension," he said.
"It took us a couple of months to come to that conclusion that we should disclose and inform all of the patients and give them the right to have a test to reassure themselves."
He said 2,497 women who had colposcopy biopsies are being sent letters advising them to have blood tests for hepatitis B, hepatitis C and HIV. Colposcopies are procedures to examine the cervix, vagina and vulva to detect cervical cancer.
Dr. Gordon Dow, an infectious disease consultant from the Moncton Hospital, said the chance of anyone contracting a virus from the unsterilized instruments is "very small" because the clinic was performing the disinfection procedure properly.
"Patients who have undergone colposcopy biopsies at the Miramichi Regional Hospital can be assured that even without sterilization, proper initial cleaning of the instrument reduces the concentration of microbes by over 99.99 per cent," Dow told the news conference.
Still, Dow said sterilization is the accepted procedure and that was not always followed.
But Dow said he is confident not a single case of infection will be detected as a result of the unsterilized forceps. He said while he expects blood tests to show that some patients have infections of hepatitis B, hepatitis C and HIV, that would be due to the prevalence of those diseases among the general population.
"If you look at these viruses among adults in Canada, the prevalence of HIV is 0.1 per cent in the general population, hepatitis C is 0.8 per cent, and hepatitis B is probably about 0.5 per cent in our part of the world," Dow said.
Health Minister Hugh Flemming said McGarry only notified him of the problem three weeks ago. Flemming said McGarry told him that a health employee who was temporarily filling in at the clinic discovered the issue.
"This person, quite properly, brought it to the attention of the supervisor and explained how they thought it should be done," Flemming said. "From that moment on that instrument was sterilized."
Flemming said he is satisfied with how the health board has handled the matter, but he added that there needs to be a stronger system of checks and balances to ensure such problems don't happen again.
"We have to go beyond just this one incident to see if there are other kinds of issues, whether it is systemic or any kinds of issues like that," Flemming said.
Liberal health critic Donald Arseneault said the priority now should be to ensure all patients are notified and given assurances about their health.
"Let's deal with it and we'll have some questions later on how this has gone on for so long," Arseneault said.