Technique to determine contamination exposure routes and the economic efficiency of folded paper-towel dispensing

Microbiological comparison of hand-drying methods: the potential for contamination of the environment, user, and bystander

BACKGROUND

The efficiency of hand drying is important in preventing pathogen spread, but knowledge surrounding which drying methods contribute least towards contamination of the environment and users is limited.

AIM

To compare the propensity of three common hand-drying methods (jet air, warm air dryers, and paper towels) to contaminate the environment, users, and bystanders.

METHODS

Hands were coated in lactobacilli to simulate poorly washed, contaminated hands, and dried. The investigation comprised 120 air-sampling tests (60 tests and 60 controls), divided into close and 1m proximity from the drying process. Separate tests used hands coated in paint to visualize droplet dispersal.

FINDINGS

Air bacterial counts in close proximity to hand drying were 4.5-fold higher for the jet air dryer (70.7 cfu) compared with the warm air dryer (15.7 cfu) (P=0.001), and 27-fold higher compared with use of paper towels (2.6 cfu) (P<0.001). Airborne counts were also significantly different during use of towel drying versus warm air dryer (P=0.001). A similar pattern was seen for bacterial counts at 1m away. Visualization experiments demonstrated that the jet air dryer caused the most droplet dispersal.

CONCLUSION

Jet air and warm air dryers result in increased bacterial aerosolization when drying hands. These results suggest that air dryers may be unsuitable for use in healthcare settings, as they may facilitate microbial cross-contamination via airborne dissemination to the environment or bathroom visitors.

The hygienic efficacy of different hand-drying methods: a review of the evidence

The transmission of bacteria is more likely to occur from wet skin than from dry skin; therefore, the proper drying of hands after washing should be an integral part of the hand hygiene process in health care. This article systematically reviews the research on the hygienic efficacy of different hand-drying methods. A literature search was conducted in April 2011 using the electronic databases PubMed, Scopus, and Web of Science. Search terms used were hand dryer and hand drying. The search was limited to articles published in English from January 1970 through March 2011. Twelve studies were included in the review. Hand-drying effectiveness includes the speed of drying, degree of dryness, effective removal of bacteria, and prevention of cross-contamination. This review found little agreement regarding the relative effectiveness of electric air dryers. However, most studies suggest that paper towels can dry hands efficiently, remove bacteria effectively, and cause less contamination of the washroom environment. From a hygiene viewpoint, paper towels are superior to electric air dryers. Paper towels should be recommended in locations where hygiene is paramount, such as hospitals and clinics.

An evaluation of hospital hand hygiene practice and glove use in Hong Kong

AIM

To identify omissions in hand hygiene practice and glove use among hospital workers in Hong Kong.

BACKGROUND

Hospital-acquired infection is the commonest complication affecting hospitalised patients. Even though research evidence suggests that hand hygiene and proper glove use are the most important ways to prevent the spread of disease and infection, compliance with both are reported to be unacceptably low.

DESIGN

An observational study of hospital workers in one acute and two convalescence and rehabilitation hospitals in Hong Kong was conducted. The participating clinical areas included the medical and surgical wards, accident and emergency department and intensive care unit.

METHODS

Hand hygiene practice and glove use amongst 206 hospital health and support workers, stratified according to years of working experience, were observed.

RESULTS

The number of observed episodes for hand hygiene was 1037 and for glove use 304. Compliance with hand hygiene was 74.7% and with glove use 72.4%. In approximately two-third of episodes, participants washed their hands after each patient contact; though, 78.5% failed to rub their hands together vigorously for at least 15 seconds. The major break in compliance with glove use was failure to change gloves between procedures on the same patient. In 28.6% of observed glove use episodes, participants did not wear gloves during procedures that exposed them to blood, body fluids, excretion, non-intact skin or mucous membranes. Significant differences in performance scores on antiseptic hand rub were found between the two types of hospital and on glove use between the three groups of work experience: ≤ 5, 6-10, >10 years.

RELEVANCE TO CLINICAL PRACTICE

Education and reinforcement of proper hand hygiene practice and glove use among hospital health and support workers is needed.

Outbreaks where food workers have been implicated in the spread of foodborne disease. Part 10. Alcohol-based antiseptics for hand disinfection and a comparison of their effectiveness with soaps

Alcohol compounds are increasingly used as a substitute for hand washing in health care environments and some public places because these compounds are easy to use and do not require water or hand drying materials. However, the effectiveness of these compounds depends on how much soil (bioburden) is present on the hands. Workers in health care environments and other public places must wash their hands before using antiseptics and/or wearing gloves. However, alcohol-based antiseptics, also called rubs and sanitizers, can be very effective for rapidly destroying some pathogens by the action of the aqueous alcohol solution without the need for water or drying with towels. Alcohol-based compounds seem to be the most effective treatment against gram-negative bacteria on lightly soiled hands, but antimicrobial soaps are as good or better when hands are more heavily contaminated. Instant sanitizers have no residual effect, unlike some antimicrobial soaps that retain antimicrobial activity after the hygienic action has been completed, e.g., after hand washing. Many alcohol-based hand rubs have antimicrobial agents added to them, but each formulation must be evaluated against the target pathogens in the environment of concern before being considered for use. Wipes also are widely used for quick cleanups of hands, other body parts, and surfaces. These wipes often contain alcohol and/or antimicrobial compounds and are used for personal hygiene where water is limited. However, antiseptics and wipes are not panaceas for every situation and are less effective in the presence of more than a light soil load and against most enteric viruses.

Outbreaks where food workers have been implicated in the spread of foodborne disease. Part 9. Washing and drying of hands to reduce microbial contamination

During various daily activities at home and work, hands quickly become contaminated. Some activities increase the risk of finger contamination by pathogens more than others, such as the use of toilet paper to clean up following a diarrheal episode, changing the diaper of a sick infant, blowing a nose, or touching raw food materials. Many foodborne outbreak investigation reports have identified the hands of food workers as the source of pathogens in the implicated food. The most convenient and efficient way of removing pathogens from hands is through hand washing. Important components of hand washing are potable water for rinsing and soaps to loosen microbes from the skin. Hand washing should occur after any activity that soils hands and certainly before preparing, serving, or eating food. Antimicrobial soaps are marginally more effective than plain soaps, but constant use results in a buildup of the antimicrobial compound on the skin. The time taken to wash hands and the degree of friction generated during lathering are more important than water temperature for removing soil and microorganisms. However, excessive washing and scrubbing can cause skin damage and infections. Drying hands with a towel removes pathogens first by friction during rubbing with the drying material and then by wicking away the moisture into that material. Paper rather than cloth towels should be encouraged, although single-use cloth towels are present in the washrooms of higher class hotels and restaurants. Warm air dryers remove moisture and any surface microorganisms loosened by washing from hands by evaporation while the hands are rubbed together vigorously; however, these dryers take too long for efficient use. The newer dryers with high-speed air blades can achieve dryness in 10 to 15 s without hand rubbing.