New research has found that hand sanitizers are not as effective as soap and water in health care settings at preventing viral outbreaks. In fact, they may even be responsible for outbreaks of seriously contagious viruses. As a common alternative to using soap and water, hand sanitizers are often regarded as being the most efficient way to cleanse hands.
More detailed investigations will be necessary though, say public health experts, to change the belief that hand sanitizers are as equally good as hand soap. For many in health care settings, the convenience of hand sanitizers greatly outweighs that of hand soap, and there are numerous recommendations encouraging their use.
In health care settings, the link between improper antibiotic use and development of super bugs is well known. The same cannot be said for the link occurring between hand sanitizers and bacterial resistance, because the link is not so clear yet.
At an American College of Preventative Medicine meeting, in February, an insightful survey on routine hand hygiene was presented. The survey focused on 161 long-term care facilities and found that the preferential use of hand sanitizers, over hand soap, was linked to a higher risk of outbreaks of the highly infectious norovirus, a virus responsible for the majority of acute gastroenteritis cases.
The study found that norovirus outbreaks were far more rampant in facilities where staff favored hand sanitizer use. In facilities where norovirus outbreaks occurred, members of staff were six times more likely to use hand sanitizers than soap and water for cleansing their hands. 53% of the facilities that reported a preference for using alcohol based hand sanitizers had confirmed norovirus outbreaks. Yet, among the 17 facilities reporting soap and water preference, only 18% had confirmed outbreaks.
In three of the facilities surveyed, that had numerous outbreaks of the norovirus, it was found that the staff were far more likely to opt for routinely using hand sanitizers instead of soap and water for hand hygiene.
According to the author of the study, Dr. David Blaney of the Epidemic Intelligence Service at the US Centers for Disease Control and Prevention (CDC), what they found shows that hand sanitizers could be “suboptimal in controlling the spread of noroviruses”. And that any casual link is non-existent due to the survey’s retrospective design.
He also went on to say that a possible reason as to why more reports of norovirus outbreaks come from care homes with a preference of using hand sanitizers, is that those homes may have a more effective infection control program, that recognizes and reports outbreaks.
Blaney then added:
“That being said, this study shows there’s a need to look at more
organism-specific outbreaks prospectively.”
Blaney says that if the prospective studies confirmed the findings, new policies concerning hand hygiene would have to be considered. An emphasis on using soap and water to wash hands instead of using sanitizers would be pursued, and also the use of disposable gloves during an outbreak.
Many studies have found the effectiveness of alcohol based hand sanitizers to be inadequate against non enveloped viruses, such as norovirus. This implies that in long term care facilities, where outbreaks are frequently experienced, hand sanitizers may not be the most appropriate form of hand hygiene.
(Appl Environ Microbiol 2010; 76:394-399 and Appl Environ Microbiol 2008;74:5047-52).
The effectiveness of alcohol based hand sanitizers against Clostridium difficile, a bacteria that causes diarrhea, was looked at in two other studies. The findings saw that many health care workers were developing spores on their hands as a result of over reliance on the sanitizers.
(Infect Control Hosp Epidemiol 2010; 31:565-70 and Infect Control Hosp Epidemiol 2009; 30:239-44).
New guidelines have been issued by the CDC for the prevention and control of norovirus. One of the new recommendations is against the use of hand sanitizer as an alternative to cleansing hands with soap and water. (
However, the CDC’s Updated Norovirus Outbreak Management and Disease Prevention Guidelines believe that while “the efficacy of alcohol-based and other hand sanitizers against norovirus remains controversial,” the evidence is not definite enough.
Aron Hall, an epidemiologist with the CDC’s division of viral diseases said:
“The findings of these studies also have to be taken in context of the benefits afforded by alcohol-based hand sanitizers and the uncertainty in their designs. We can, however, strongly recommend more prospective studies to evaluate the issue further.”
Another epidemiologist with the CDC’s division of health care quality promotion, Kate Ellingson, said that hand sanitizers are commonly used among medical professionals as it is a convenient means of cleansing the hands. She said that:
“Hand sanitizer is promoted so widely because it’s efficient, accessible and takes relatively very little time to use. There’s potentially a large tradeoff in switching back to soap and water in the health care setting, where workers have to wash their hand many, many times per shift, or even hour, depending on what they’re doing.”
Ellingson pointed out that the key to understanding risks associated with sanitizers is to carry out further trials:
“If some kind of association was found through more rigorous trials, we would want to better understand the particular indications when the risk was highest so as not to totally throw the baby out with the bathwater.”
Written by Joseph Nordqvist