In the News
The use of alcohol-based hand sanitizers (ABHSs) in health care settings has become widespread since 2002, when the Centers for Disease Control and Prevention (CDC) recommended ABHSs for patient contact except when hands are physically soiled. But ABHSs aren't effective against certain categories of pathogens, including noroviruses and Clostridium difficile. The question has therefore been raised whether overreliance on ABHSs has played a role in precipitating disease outbreaks or in creating more virulent strains of these pathogens.
Finding the right answer to this question is urgent, given the severe impact of these diseases: 94% of C. difficile infections are connected to medical care, and between 2000 and 2007 C. difficile–related deaths increased by 400%. According to 2012 CDC data, 14,000 Americans die annually from C. difficile diarrhea.
In addition, highly infectious noroviruses are suspected as the causative agent in more than 23 million U.S. gastroenteritis cases annually and cause approximately 60% of all acute gastroenteritis cases. From December 2006 to March 2007, marked increases occurred in norovirus illnesses across the United States in general, all associated with two new strains.
Outbreaks in long-term care. A 2011 study in long-term care facilities that experienced norovirus outbreaks showed that facilities whose staff used ABHSs as often as or more often than soap and water were six times more likely to experience an outbreak.
The CDC therefore modified its guidelines for hand hygiene, recommending that during outbreaks of norovirus and C. difficile health care workers use soap and water when in contact with patients (in addition to isolation, environmental disinfection, and gloving when treating them). The question remains: did the prevalent use of ABHSs rather than soap and water cause these outbreaks?
Aron Hall, a norovirus expert and epidemiologist at the CDC's Division of Viral Diseases, believes that wasn't the case with norovirus, noting that “noroviruses mutate quite frequently. Every year a new strain emerges, replaces its predecessor as the predominant strain in circulation.” There's really no evidence, he says, that ABHSs exert a selective pressure on the evolution of more virulent strains.
Similarly, Clifford McDonald, a C. difficile authority and senior adviser for science and integrity at the CDC's Division of Healthcare Quality Promotion, says there's no convincing evidence that ABHSs have played a role in C. difficile outbreaks or strain selection. “All available evidence suggests that it was the widespread use of the fluoroquinolone antibiotics that had a role in the emergence and spread of NAP1 [a virulent and predominant epidemic strain].”
McDonald recommends against further changes in CDC guidelines so that the significant progress ABHS use has brought about in reducing health care–associated infections won't be lost.
But what is the right overall balance for hand hygiene? The CDC notes that adherence to proper hand hygiene can be increased through ongoing education, reminding staff to rub all hand surfaces for 40 to 60 seconds with soap and water or 20 to 30 seconds with 3 to 5 mL of alcohol (at least).—David Carter
Blaney DD, et al. Am J Infect Control 2011; 39(4):296-301; Blossom DB, McDonald LC Clin Infect Dis. 2007;45(2):222–7