In an editorial published in
JAMA last October, William A. Rutala, PhD, MPH, Professor of Medicine,
University of North Carolina School of Medicine, Chapel Hill; Director, North
Carolina Program for Infection Control and Epidemiology; Director, Hospital
Epidemiology, Occupational Health and Safety Program Hospital Epidemiology,
University of North Carolina Health Care; and David J. Weber, MD, MPH,
Professor of Medicine, Division of Infectious Diseases, University of North
Carolina School of Medicine, Chapel Hill, stated that the margin of safety associated
with cleaning and high-level disinfection of gastrointestinal endoscopes is 0-2
log
10. Rutala WA, Weber DJ.
Gastrointestinal endoscopes: a need to shift
from disinfection to sterilization?
JAMA. 2014 Oct 8;312(14):1405-6.
PMID: 25291575. Rutala and Weber compared this low margin of safety to the 17
log
10 margin of safety associated with cleaning and sterilization of surgical
instruments.
But I had no idea how 2 log10 compared to 17log10. Bob explained
that, at best, the margin of safety of endoscope reprocessing is 15 to 17
orders of magnitude less than the margin of safety for reprocessing of surgical
instruments. Not 15 to 17 times less. 15 to 17 orders of magnitude less. That
is literally over a quadrillion times less. So, the margin of safety associated with the cleaning protocol for duodenoscopes recommended in instructions provided by the manufacturer (Olympus Corporation) and the FDA is over a quadrillion times less than the margin of safety for reprocessing surgical instruments.