Outside health experts stress low infection risk from YKHC dental instruments
The Yukon Kuskokwim Health Corporation is testing patients for Hepatitis B, C, and HIV after partially sterilized dental instruments were used on patients. Out of the 191 patients seen during the nine-day period in question, up to 13 patients might have had contact with the instruments. When YKHC discovered the error, they consulted with the Alaska Section of Epidemiology and the Center for Disease Control. KYUK talked to some of the same people.Listen Now The YKHC Dental Clinic is the lower level row of windows to the right of the entrance. (Photo by Dean Swope – KYUK, Bethel)Here are two of the people YKHC talked to: Louisa Castrodale, epidemiologist with the Alaska Section of Epidemiology, Division of Public Health and Dr. Joseph Perz. epidemiologist with the CDC Division of Health Care Quality Promotion.When asked about the risk of infection, both said the same thing:“This is a situation where the chances are rather low, and maybe even theoretical, that there would have been an exposure,” Castrodale said.“This is something that in our risk assessment poses a very, very, low, theoretical risk of infection,” Perz echoed.It’s a theoretical risk, because it’s not known if any of the instruments were contaminated with Hepatitis B, C, or HIV.First, the instruments would have had to have been used on a person who carried one of those viruses. Second, the instruments would have had to have retained some blood. Third, the virus would have had to survive the first two steps of the three-step cleaning process: detergent and ultrasound. YKHC just missed the last step: heat.Susan Jones is the HIV/STD Program Manager for the Alaska Section of Epidemiology. She didn’t talk to YKHC, but she thinks the cleaning that did happen was enough to kill HIV, which was highly unlikely to be on the instruments anyway.“We have very few new infections a year, and very few folks that have infections who live in Alaska,” Jones said.So few, that last year there were only 64 cases of HIV reported in the state. None were in Southwest Alaska.With Hepatitis C, 91 cases were reported in Southwest Alaska last year, and no cases of Hepatitis B were reported in the area.There’s no vaccination for HIV or Hepatitis C, but most people get vaccinated against Hepatitis B as infants. In fact, a National Immunization Survey showed that between 2000 and 2001, 90 percent of Alaska Native infants were vaccinated against Hepatitis B.So few people in the region even have these illnesses to pass on, and the viruses don’t do well outside the body.“Hepatitis B is an example where experimental studies have shown that the virus remains viable for weeks, potentially, in the environment,” Perz explained. “Hepatitis C is more medium level in that regard, so its viability would be measured in hours or days. And HIV is thought to be the least hardy of those three, so it might only survive a very short while on an inanimate surface.”A CDC study showed just drying HIV caused a 90 to 99 percent reduction in concentration within several hours.“I would say, again, in this situation,” Perz said, “patients can be reassured that there was very little risk.”“But it’s not zero,” Castrodale warned. “And so the decision was made to continue to reach out to those patients.”YKHC wasn’t required to contact patients and tell them what happened or to offer free blood tests. Perz calls their situation a gray zone, but one where transparency is encouraged and one where it was chosen.To anyone who got one of those calls, he offers this way to look at it:“Thirteen patients might have been exposed to these instruments. There are actually 191 patients who’re sort of in the risk pool. That translates to 178 patients who have zero risk at all. I would say for the remaining 13 patients, the risk is so low, it is to be close to negligible.”The take away is that few people in the area have the viruses to pass on; and the viruses probably couldn’t survive the initial cleaning process; but a risk still exists. So, as HIV/STD Program Manager Susan Jones said, “Get tested.”Anyone with medical questions can talk to a nurse by calling YKHC at 1-844-543-6361.