Superbugs Found Resistant to Alcohol-Based Disinfectants
Researchers in Australia have found the ‘superbug’ Enterococcus faecium has become more resistant over the past 19 years to alcohols widely used in both handwashing formulas and surface disinfection wipes. The bacterial strains today were found to be more resistant by a factor of 10. The findings suggest that bacteria adaptation is complicating infection control recommendations and require additional procedures to be put in place to prevent E. faecium from spreading in hospitals.
Some Enterococcus strains can survive on a surface for over 4 months. 50% of these bacteria are resistant to the antibiotic vancomycin and are thus classified as vancomycin-resistant enterococci (VRE). ‘Costs associated with patients infected with VRE are high due to the need for isolation rooms, specialized cleaning regimens, and the impact on staff, bed availability, and other resources.’Enterococcus infections now account for about 10% of all hospital-acquired infections globally. They are also the fourth and fifth leading cause of sepsis, a life-threatening condition due to infections, in North America and Europe.
The implications of this study are vast and potentially alarming. The FDA recommends hand sanitizers with at least 60% alcohol and many of the most popular wipes designed and advertised for use with touchscreens also contain high percentages of alcohol. This suggests that procedures relying on wipes alone to both clean and disinfect be reviewed. It is important to distinguish that disinfection is different than cleaning in that disinfection is the killing of pathogens and cleaning is the removal of dirt and grime.
Every chemical has a spectrum of bacteria it is designed to kill within a specified contact time anywhere between 1 and 10 minutes. If the bacteria on a device is not on the list of organisms that the chemical is designed to kill, it may not be entirely effective. In the case of this study, the presence of alcohol, normally expected to kill many different types of bacteria strains may now be in question.
UV-C light offers an indiscriminate alternative to killing pathogens as UV-C causes damage to all nucleic acids and proteins in its path.
References
Increasing tolerance of hospital Enterococcus faecium to handwash alcohols By Sacha J. Pidot, Wei Gao, et al. Science Translational Medicine Aug 2018
Selective Photonic Disinfection: A Ray of Hope in the War Against Pathogens By Shaw-Wei D Tsen, Kong-Thon TsenNeely AN, Maley MP.
Survival of Enterococci and Staphylococci on Hospital Fabrics and Plastic. Journal of Clinical Microbiology. 2000;38(2):724-726.Wendt C, Wiesenthal B, Dietz E, Rüden H.
Survival of Vancomycin-Resistant and Vancomycin-Susceptible Enterococci on Dry Surfaces. Journal of Clinical Microbiology. 1998;36(12):3734-3736.https://www.cdc.gov/handwashing/show-me-the-science-hand-sanitizer.html