Nearly 2,500 women who underwent biopsies at the Miramichi Regional Hospital's colposcopy clinic in New Brunswick may be at risk of HIV and other infections because standard sterilizing procedures weren't always followed over a 14-year period, Horizon Health Network officials say.

The 2,497 current and former patients who had the procedure will receive a registered letter in the mail, offering that they have blood tests to check for HIV, hepatitis C and hepatitis B as a precaution, said Dr. Gordon Dow, an infectious disease specialist.

Miramichi Regional Hospital's colposcopy clinic in New Brunswick has not been following sterilization standards in all cases for the past 14 years, officials announced on Wednesday. (CBC)

He emphasized, however, that the risk of infection is "very, very small."

"I am very confident there will not be a single case of infection acquired through this process," Dow said during a news conference Wednesday.

"However, we will discover some cases" of the infections, based on their prevalence in the general population, he said, adding: "So we will identify people, but none of those people would have acquired their infection through the process."

A colposcopy is a diagnostic procedure used to closely examine a woman's cervix, vagina and vulva for signs of disease, such as cancer. It is often performed if a Pap test has come back with abnormal results.

Employee flagged sterilization issue

Horizon Health Network president and CEO John McGarry apologized for the error and the apprehension it may cause for patients. (CBC)

The forceps used during biopsies between May 1999 and May 24, 2013, were not always sterilized in accordance with the North American standard, which has been in place for more than 50 years, officials said.

In some cases, the instruments were put through a high-level disinfection process instead.

High-level disinfection is a process used to remove to kill "most germs" from medical instruments that come into contact with mucus membranes or blood, said Dow. It is achieved through various processes, such as pasteurization or by using chemical products.

Sterilization is a process used to remove or kill "all forms of germs," by using steam, gas, or chemicals, he said.

High-level disinfection destroys "99.99 per cent of blood-borne pathogens such as hepatitis B, hepatitis C and HIV," stressed Dow.

"The estimated risk of contracting hepatitis B is 1 in 47,000 procedures; however, the risk of becoming ill is 1 in 156,000 procedures," he said.

"The risk of contracting hepatitis C or HIV is less than one in a million procedures when using high-level disinfection cleaning."

In fact, Dow said a review of medical literature found no cases where high-level disinfection — when properly carried out —resulted in the transmission of any of the viral infections.

The high-level disinfection process at the Miramichi clinic was audited and was "carried out perfectly … according to manufacturer's guidelines," he said.

Horizon Health Network president and CEO John McGarry said an employee flagged the issue and the process was corrected immediately.

Asked why patients are only being notified now when the problem was discovered three months ago, McGarry said: "Given that this was a 14-year issue and it wasn’t a case of something needed to be decided right that day, 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 in communities and individuals and we want to understand that as we go forward.

"So it took us a couple of months to come to that conclusion that we should disclose, we should inform all of the patients and give them the right to have a test to reassure themselves."

Shortage of forceps

McGarry said the problem started 14 years ago when patient volumes at the clinic grew and there weren't enough forceps for the number of patients seen during a day.

All the instruments would be sterilized the night before, but a few would have been "reprocessed" during the day to meet the demand, he said.

"A decision was made in that regard. It just wasn't picked up for 14 years."

McGarry declined to identify who made that decision. "We're not considering disciplinary action at this time," he said.

Although 2,497 patients are being notified, "there’s a good chance that half of those people had a sterilized instrument to begin with," said McGarry.

Only women who had biopsies at the clinic before May 24 are considered at risk, he stressed.

"If you do not receive a letter within the next five to seven days, then you have not been affected and are at no risk," he said.

Vitalité reviewing its procedures

Horizon officials have confirmed all other sites are following the recommended sterilization process, said McGarry.

Colposcopy clinics are offered at four additional hospitals, including the Dr. Everett Chalmers Regional Hospital in Fredericton, the Saint John Regional Hospital, the Moncton Hospital and the Katherine Wright Centre, also in Moncton, according to the regional health authority's website.

Horizon has also contacted the Vitalité Health Network to "be sure that they check their procedures to assure themselves that they're following the proper process and that's been underway for the past week, I understand," said McGarry.

"Again, 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," he said.

"I, on behalf of everyone at Horizon, apologize for this error and the resulting apprehension this news may cause our patients."