Wednesday, August 10, 2011

CMAJ: Hand Sanitizers May Be `Suboptimal’ For Preventing Norovirus



Photo Credit – CDC


# 5747


While dispensers of alcohol-based hand sanitizers have become ubiquitous in many health care facilities over the past few years, there remain serious questions over just how effective they may be in killing some particularly hearty pathogens.


In recent years it has become apparent that alcohol based hand cleansers are not effective at killing the spores of the Clostridium difficile bacteria, and so the CDC offers this advice:


How can Clostridium difficile infection be prevented in hospitals and other healthcare settings?

  • Use gloves when entering patients’ rooms and during patient care.
  • Perform Hand Hygiene after removing gloves.
  • Because alcohol does not kill Clostridium difficile  spores, use of soap and water is more efficacious than alcohol-based hand rubs. However, early experimental data suggest that, even using soap and water, the removal of C. diffile spores is more challenging than the removal or inactivation of other common pathogens.
  • Preventing contamination of the hands via glove use remains the cornerstone for preventing Clostridium difficile transmission via the hands of healthcare workers; any theoretical benefit from instituting soap and water must be balanced against the potential for decreased compliance resulting from a more complex hand hygiene message.


And more recently, we’ve seen increased evidence that these handy hand sanitizers may be `suboptimal’ at killing some nonenveloped viruses (including norovirus), as well.


In March of this year, the CDC’s MMWR published a lengthy report that called into question the efficacy of alcohol based products against norovirus:


Updated Norovirus Outbreak Management and Disease Prevention Guidelines


Overall, studies suggest that proper hand washing with soap and running water for at least 20 seconds is the most effective way to reduce norovirus contamination on the hands, whereas hand sanitizers might serve as an effective adjunct in between proper handwashings but should not be considered a substitute for soap and water handwashing.


Today, the CMAJ has an early release news item that summarizes the findings of a couple of recent studies that showed that health care facilities that relied more heavily on alcohol-based sanitizers were more apt to experience outbreaks of norovirus.



Hand sanitizers may increase norovirus risk

August 10, 2011


Alcohol-based hand sanitizers may not be the panacea for hand hygiene they were once supposed, as mounting research indicates they may not be effective substitutes for soap and water, and in some cases may actually increase the risk for outbreaks of highly contagious viruses in health care settings.


Public health experts, however, say more rigorous investigations will be necessary to trump the convenience of using hand sanitizers, among other benefits, or substantially alter existing recommendations that strongly encourage their use by health care professionals.

(Continue . . . )


You can read the abstract to one of these studies in the May 2011 edition of the  AJIC.


Use of alcohol-based hand sanitizers as a risk factor for norovirus outbreaks in long-term care facilities in northern New England: December 2006 to March 2007


David D. Blaney, MD, MPH , Elizabeth R. Daly, MPH , Kathryn B. Kirkland, MD ,Jon Eric Tongren, PhD, MSPH , Patsy Tassler Kelso, PhD , Elizabeth A. Talbot, MD


Lead author Dr. David Blaney of CDC’s  Epidemic Intelligence Service is quoted in the CMAJ article as saying that alcohol-based hand sanitizers might be, “suboptimal in controlling the spread of noroviruses.”


For now, the efficacy of alcohol based hand sanitizers against norovirus remains controversial at best. More, and better studies will be needed before any firm conclusions can be drawn.


None of this is to suggest that hand sanitizers are without value.


They are fast and easy - which promotes their frequent use - and when used properly they appear effective against a wide variety of bacteria and enveloped viruses, including colds and influenzas.



But when dealing with a norovirus outbreak, for now the best policy appears to be washing your hands thoroughly with soap and water.

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