Inter-laboratory reproducibility of the hand disinfection reference procedure of EN 1500

Recent tests carried out using EN 1500 have suggested that most alcohol-based hand gels are significantly less effective than the reference alcohol [2-propanol, 60% (v/v)] whereas liquid alcohol-based hand rubs are not. However concerns about the accuracy and reproducibility of the test have been raised. We therefore analysed 41 experiments performed in four different laboratories using EN 1500 hand disinfection procedures with the reference alcohol, to analyse inter-laboratory reproducibility of the test. The mean reduction factors (difference of the log(10) of the pre-value and the post-value) from the four laboratories did not reveal a significant difference (P=0.059; analysis of variance), although the difference of the mean pre and post-values was highly significant (P<0.001). EN 1500 is a reproducible test method which leads to valid data.     

Spectrum of antimicrobial activity and user acceptability of the hand disinfectant agent Sterillium Gel

The antimicrobial efficacy of alcohol-based hand gels has been shown to be significantly less than liquid hand rubs probably because of a lower concentration of alcohol. Sterillium Gel is the first hand gel with 85% ethanol. Its antimicrobial efficacy and user acceptability was studied. Bactericidal activity was tested according to prEN 12054 against Staphylococcus aureus, Enterococcus hirae, Pseudomonas aeruginosa and Escherichia coli (suspension test) and EN 1500 (15 volunteers; four replicates), fungicidal activity according to EN 1275 against Candida albicans and spores of Aspergillus niger (suspension test) and tuberculocidal activity against Mycobacterium terrae using the DGHM suspension test. Virucidal activity was determined in suspension tests based on reduction of infectivity with and without interfering substances (10% fetal calf serum; 0.3% erythrocytes and 0.3% bovine serum albumin). Ninety-six healthcare workers in hospitals in France and the UK used the gel for four weeks and assessed it by filling out a questionnaire. The gel was bactericidal (a reduction factor of > 10(5)-fold), tuberculocidal (reduction factor > 10(5)) and fungicidal (reduction factor > 10(4)) in 30 s. Irrespective of interfering substances the gel inactivated orthopoxvirus and herpes simplex virus type 1 and 2 in 15 s, adenovirus in 2 min, poliovirus in 3 min and papovavirus in 15 min by a factor of > 10(4)-fold. Rotavirus and human immunodeficiency virus were inactivated in 30 s (without interfering substances). Under practical use conditions it was as effective in 30 s as the reference alcohol in 60 s. Most users described the tackiness, aggregation, skin feeling after use and smell as positive or acceptable. A total of 65.6% assessed the new gel to be better than a comparator irrespective of its type (gel or liquid). Overall Sterillium Gel had a unique spectrum of antimicrobial activity. It is probably the first alcohol-based hand gel to pass EN 1500 in 30 s. Due to the excellent acceptance by healthcare workers it may significantly improve compliance for hand hygiene and thereby help to reduce the incidence of nosocomial infection.     

Efficacy of 2 alcohol-based gels and 1 alcohol-based rinse for surgical hand disinfection.

We assessed the efficacy of 2 alcohol-based gels and 1 alcohol-based rinse for surgical hand disinfection, using European standard EN 12791. Volunteers performed surgical hand disinfection with a reference product and each of the 3 study products, with 1-week intervals between disinfection episodes. The immediate and sustained antimicrobial activities of each study product were not significantly less than those of the reference product. The study products passed the efficacy requirements of the EN 12791 standard, and they are considered suitable for surgical hand disinfection.     

Intra-laboratory reproducibility of the hand hygiene reference procedures of EN 1499 (hygienic handwash) and EN 1500 (hygienic hand disinfection)

The bactericidal efficacy of hand antiseptic products is determined in Europe using two norms--EN1499 (hygienic handwash), and EN 1500 (hygienic hand disinfection) based on reducing the counts of bacteria on artificially contaminated hands. Each requires 12-15 data sets per test and comparison with a reference procedure. Recent research using EN 1500 suggested that most alcohol-based hand gels are significantly less effective than the reference alcohol (2-propanol 60%), whereas liquid alcohol-based rubs are not. However concerns about the accuracy and reproducibility of the norm reference procedures have been raised. We therefore analysed 23 experiments carried out using EN 1500 representing 342 hand disinfection procedures, and 12 experiments using EN 1499 representing 178 handwashes, all performed in the same laboratory for reproducibility of the reference procedures. The reference alcohol gave a mean log(10) reduction factor (RF) of 4.64 +/- 0.93; only one data set gave a significantly higher result (5.14, P = 0.034), and one significantly lower (4.05; P = 0.034). Analysis of all 23 means revealed no significant difference (P = 0.188; ANOVA model). The reference soap gave a mean reduction of 2.82 +/- 0.49. Two data sets were significantly higher than this (3.35,P < 0.001; 3.12, P < 0.001) and two significantly lower (2.55, P = 0.031; 2.47,P = 0.004). Analysis of all the means did reveal a significant difference (P < 0.001, ANOVA model), which is probably explained by the smaller standard deviations of these results. Pre-values (bacteria recovered from fingers before a reference procedure) correlated significantly with RFs for both hand disinfection (correlation coefficient: 0.291;P = 0.01) and handwash (correlation coefficient: 0.372, P = 0.01). Overall both procedures gave accurate and reproducible results.     

Suitability of Sterillium Gel for surgical hand disinfection

In some countries, alcohol-based hand gels are used for hygienic hand disinfection but their efficacy and suitability for surgical hand disinfection has never been investigated. The efficacy of Sterillium Gel was investigated according to prEN 12791 in two separate experiments. Finger tips of 20 volunteers per experiment were sampled for resident skin bacteria before surgical hand disinfection. In a cross-over design, each volunteer carried out a surgical hand disinfection with the reference alcohol [n-propanol 60%, (v/v)] or Sterillium Gel [ethanol 85% (v/v)] for 3 min. After the product application, one hand was sampled for the immediate effect, the other hand was gloved for 3 h and then sampled for the sustained effect. Samples were analysed for remaining resident bacteria. The mean of the pre-value, the 0 h and 3 h values of the reference disinfection and the test product were calculated. With the reference alcohol, respective mean immediate log10-reduction factors of 2.06+/-0.76 and 2.23+/-1.13 were found in both experiments. The mean sustained effects with the reference alcohol were 2.03+/-1.14 and 1.44+/-0.81. Sterillium Gel achieved respective mean immediate effects of 2.48+/-1.06 and 2.13+/-0.81, the mean sustained effects were 2.77+/-0.95 and 2.18+/-0.72. They proved significantly larger than those obtained with the reference alcohol (P<0.05; pair-wise Wilcoxon test). Sterillium Gel, therefore, more than fulfils the efficacy requirements for surgical hand disinfection of prEN 12791. In addition, 25 of 26 operating theatre healthcare workers in an orthopaedic hospital found it suitable for surgical hand disinfection after a single use, which included putting on a pair of surgical gloves. Although none of them had ever used an alcohol-based gel before, they had rather been accustomed to alcohol-based liquid products for years. The main reasons given for the positive assessment were better skin feeling after use, smell and easier donning of the surgical gloves. No significant correlation was found between overall or dermal acceptance and years of professional experience, profession or number of gel portions used for surgical hand disinfection (Pearson's correlation; P>0.05).     

Comparison of waterless hand antisepsis agents at short application times: raising the flag of concern.

OBJECTIVE: Although alcohol-based hand rinses and gels have recommended application times of 30 to 60 seconds, healthcare workers usually take much less time for hand hygiene. We compared the efficacies of four alcohol-based hand rubs produced in Europe (hand rinses A, B, and C and one gel formulation) with the efficacy of the European Norm 1500 (EN 1500) reference waterless hand antisepsis agent (60% 2-propanol) at short application times. DESIGN: Comparative crossover study. SETTING: Infection Control Program laboratory of a large tertiary-care teaching hospital. PARTICIPANTS: Twelve healthy volunteers. INTERVENTION: Measurement of residual bacterial counts and log reduction factors following inoculation of fingertips with Staphylococcus aurens American Type Culture Collection (ATCC) 6538, Pseudomonas aeruginosa ATCC 15442, and a clinical isolate of Enterococcus faecalis. RESULTS: All hand rinses satisfied EN 1500 standards following a single application for 15 and 30 seconds, but reduction factors for the gel formulation were significantly lower for all tested organisms (all P < .025). CONCLUSIONS: Under stringent conditions similar to clinical practice, all three hand rinses proved to be more efficacious than the marketed alcohol-based gel in reducing bacterial counts on hands. Further studies are necessary to determine the in vivo efficacy of alcohol-based gels and whether they are as efficacious as alcohol-based rinses in reducing the transmission of nosocomial infections.     

Comparison of two test methods for the determination of sufficient antimicrobial activity of three commonly used alcohol-based hand rubs for hygienic hand disinfection

In Europe, the antimicrobial efficacy of alcohol-based hand rubs is determined with a quantitative suspension test (prEN 12054) and a test under practical conditions (EN 1500). Another test method has recently been published by the German Society for Hygiene and Microbiology (DGHM) with four differences to the European system in the in vitro tests: additional qualitative suspension tests with product dilutions to the ineffective range; a selection of the most resistant Gram-negative test strains in the qualitative suspension test, which should be used adjacent to Pseudomonas aeruginosa in the quantitative suspension test; a high organic load in the quantitative suspension tests (0.3% albumin and 0.3% sheep erythrocytes); and an aqueous control in the quantitative suspension test. According to DGHM, the in vitro tests should be followed by EN 1500. We have determined the antimicrobial efficacy of three commonly used alcohol-based hand rubs according to both methods. prEN 12054 was carried out without organic load. The qualitative suspension tests (DGHM) were carried out with P. aeruginosa, Escherichia coli, Proteus mirabilis, Staphylococcus aureus, Enterococcus hirae and Candida albicans. The quantitative suspension test (DGHM) was carried out with product dilutions of 75%, 50% and 25%, and a high organic load using the following test organisms: P. aeruginosa, P. mirabilis (one product only), S. aureus, E. hirae and C. albicans. All these suspension tests were carried out in quadruplicate with each product and exposure time. EN 1500 was carried out with 3 mL of each product and an application time of 30 s. All three products achieved the required bactericidal activity of prEN 12054 and the new DGHM method within 30 s, and were equally effective with the reference hand disinfection of EN 1500 within 30 s. In our study, the DGHM test method did not provide additional information for hand rubs which exhibit their bactericidal efficacy with 3 mL within 30 s (EN 1500).     

Effect of a 1 min hand wash on the bactericidal efficacy of consecutive surgical hand disinfection with standard alcohols and on skin hydration

BACKGROUND: In most surgical theatres, a 1 min or even longer hand wash is routine as part of the pre-operative hand disinfection. But its benefit has recently been seen critically. METHODS: We have therefore investigated the effect of a 1 min hand wash on skin hydration and on the efficacy of consecutive surgical hand rubbing with three standard alcohols (60% propan-1-ol, 60% propan-2-ol, 80% ethanol; all v/v) on the resident hand flora. Three types of treatment were performed: (i) a 1 min pre-wash before surgical hand disinfection, (ii) no pre-wash before surgical hand disinfection and (iii) no pre-wash but use of a brush for 1 min during disinfection procedure. The efficacy of the alcohols was determined according to prEN 12791 with the same 20 volunteers in paired groups. To assess the effect of the hand wash on skin hydration, 10 volunteers washed their hands with sapo kalinus for 1 min and dried hands with a paper towel. Skin hydration was measured with a corneometer before the hand wash and subsequently up to 10 min thereafter both on the palm and dorsum of hands. We also tested the reduction of bacterial spores by a 15 s hand wash according to EN 1499 after artificial contamination of hands of 14 volunteers with spores of B. stearothermophilus. RESULTS: Propan-1-ol (60%) was most effective with a mean log10 reduction of 2.11, followed by ethanol (80%) with a mean log10 reduction of 1.76 and propan-2-ol (60%) with a mean log10 reduction of 0.57 (all immediate effect without hand wash). The efficacy of the alcohols was neither significantly improved nor impaired by a preceding 1 min hand wash, but there is a trend towards better efficacy on dry hands. Using a brush for 1 min during disinfection resulted in a better efficacy with all alcohols. An anaylsis of variance revealed that the immediate effect of ethanol (p = 0.013) and propan-2-ol (p = 0.001) is significantly influenced by the variation of treatments which is mainly explained by the effect of brushing during disinfection. But no significant difference between treatment variations was found in the sustained effect with any of the alcohols. Skin hydration increased significantly by a 1 min hand wash for up to 10 min despite drying hands with a paper towel. A 15 s hand wash reduced the number of bacterial spores significantly from log10 3.84 to log10 1.99 (p = 0.001). CONCLUSIONS: There is no benefit of a hand wash as part of surgical hand disinfection except that a short hand wash of 15 s can effectively reduce spores. The best time for this short hand wash is at the beginning of work in hospital, but at the latest in the sluice of the operating theatre about 10 min before applying an alcohol-based hand rub to give the skin enough time to dry.     

Testing of the World Health Organization-recommended formulations for surgical hand preparation and proposals for increased efficacy

The 2009 World Health Organization (WHO) Guidelines on hand hygiene in health care recommend alcohol-based hand rubs for both hygienic and pre-surgical hand treatment. Two formulations based on ethanol 80% v/v and 2-propanol 75% v/v are proposed for local preparation in healthcare settings where commercial products are not available or too expensive. Both formulations and our suggested modifications (using mass rather than volume percent concentrations) were evaluated for their conformity with the efficacy requirements of the forthcoming amendment of the European Norm (EN) 12791, i.e. non-inferiority of a product when compared with a reference procedure (1-propanol 60% v/v for 3 min) immediately and 3 h after antisepsis. In this study, the WHO-recommended formulations were tested for 3 min and 5 min. Neither formulation met the efficacy requirements of EN 12791 with 3 min application. Increasing the respective concentrations to 80 w/w (85% v/v) and 75 w/w (80% v/v), together with a prolonged application of 5 min, rendered the immediate effect of both formulations non-inferior to the reference antisepsis procedure. This was not the case with the 3h effect, which remained significantly inferior to the reference. Although the original formulations do not meet the efficacy requirements of EN 12791, the clinical significance of this finding deserves further clinical trials. To comply with the requirement of EN 12791, an amendment to the formulations is possible by increasing the alcohol concentrations through changing volume into mass percent and prolonging the duration of application from 3 min to 5 min.     

Dermatological aspects of a successful introduction and continuation of alcohol-based hand rubs for hygienic hand disinfection

With the new Centers for Disease Control and Prevention (CDC) guideline on hand hygiene, hospitals often introduce alcohol-based hand rubs for hand disinfection. Healthcare workers, however, may reject the new products because of skin irritation or other skin-related problems, which they experience after years of handwashing. In order to facilitate a successful introduction and continued use of alcohol-based hand rubs in hospitals, we have reviewed and summarized the major studies on the topic. Occupational hand dermatitis may occur in up to 30% of healthcare workers. It is mainly described as an irritant contact dermatitis caused by detergents. The diagnosis is usually clinical. Allergic reactions are very rare. After using an alcohol-based hand rub for the first time, healthcare workers may have a burning skin sensation that can be explained by pre-irritated skin. In this case the skin barrier has usually been impaired by frequent handwashing or occlusive gloves. This may result in a vicious circle whereby the healthcare worker increases the frequency of handwashing and reduces the frequency of hand disinfection. Prevention of irritant contact dermatitis is possible by selection of a low-irritating hand rub, which contains emollients, the correct use of the hand rub and a clear guideline when to disinfect and wash hands in the clinical setting. Common mistakes in the use of alcohol-based hand rubs are application to pre-irritated skin and washing hands before hand disinfection, which is, in general, not necessary, or after hand disinfection, which results in washing off the emollients. Clear preparation and guidance of healthcare workers before the introduction of alcohol-based hand rubs can help to enhance compliance in hand hygiene. The switch from handwash to alcohol-based hand rub will improve healthcare workers skin if mistakes are avoided and hand rinses are used correctly.     

Improving adherence to surgical hand preparation

At present, no universal agreement on detailed practice for surgical hand preparation exists. In order to fill this gap, in 2002 a Franco-German recommendation for surgical hand preparation was published as a first step towards a generally accepted European recommendation. Based on an assessment of the actual literature, a protocol for surgical hand preparation is discussed with the aim to recommend evidence-based standard procedures including prerequisites, washing and disinfection phase, and its practical implementation. In contrast to hygienic hand disinfection, for surgical hand preparation compliance is not an issue, since it mostly is regarded as a ceremony which is carried out without exception. Nevertheless, the following factors influence acceptance and efficacy: skin tolerance, ease of use, duration of procedure, and recommended time), potential for impaired efficacy due to incorrect performance of the procedure, possibility of systemic risks and irritating potential by applied preparations, religious restrictions, ecological aspects, costs and safety. Here, we report our experience with the introduction of a new hand preparation regime in all surgical disciplines in our university hospital based on the above factors. The following statements were evaluated: 1) The immediate efficacy of an alcohol-based hand disinfectant is impaired by a preceding hand wash for up to 10 minutes. Therefore hands should not be routinely washed before the disinfection period unless there is a good reason for it such as visible soiling. 2) A shortened application time (1.5 minutes) is equal to 3 min in terms of efficacy. 3) Hands should be air dried before gloves are put on, otherwise the perforation rate of gloves will increase. 4) The efficacy of alcohol-based disinfectants is significantly higher when hands are allowed to dry for 1 minute after the washing phase and before the disinfection phase. To clarify the above questions before the establishment of the modified technique, the surgical team was invited to a meeting. As a result, the heads of surgical departments supported the new technique and decided to change their practice.     

In-vivo efficacy of hand sanitisers against feline calicivirus: a surrogate for norovirus

Hand disinfection is considered important in preventing the transmission of viruses, including norovirus. We investigated the virucidal efficacy of nine hand sanitisers (four alcohol-based sanitisers, three non-alcoholic sanitisers and two triclosan-containing antimicrobial liquid soaps) against feline calicivirus, a surrogate for norovirus, on artificially contaminated fingertips for 30 s and 2 min contact periods. Among alcohol-based sanitisers, a product containing 99.5% ethanol was more effective than those containing 62% ethanol, 70% isopropanol or 91% isopropanol. A log(10) virus reduction factor of 1.00-1.30 was achieved with 99.5% ethanol but those containing a lower alcohol concentration only achieved a log(10) reduction factor of 相似文献   

Evaluation of the bactericidal effect of five products for surgical hand disinfection according to prEN 12054 and prEN 12791

Surgical hand disinfection (with an alcohol-based hand rub) and surgical handwash (with an antiseptic-based liquid soap) are accepted measures to reduce the risk for surgical site infections. The new European Standards allow a comparison of their antimicrobial efficacy. The bactericidal activity of surgical hand rubs [Sterillium and Softaman, (active ingredient=alcohols)] and handwashes [Derman plus (triclosan), Hibiscrub (chlorhexidine) and Betadine (PVP-iodine)] was tested according to the prEN 12054 suspension test using Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus hirae, and to prEN 12791 for the effect on resident skin flora in comparison with 1-propanol, 60% (v/v). All five products achieved a reduction of test bacteria within 3 min of >10(5)-fold so fulfilling prEN 12054. However, only Hibiscrub, Sterillium and Softa Man met the requirements of prEN 12791, giving a mean reduction of resident micro-organisms (immediate and sustained effect) which was not significantly lower than the reference alcohol (P>0.1; Wilcoxon matched-pairs signed-rank test). Sterillium was significantly more effective than the reference alcohol (immediate and sustained affect). Products for surgical hand disinfection may have equal antimicrobial activity in suspension tests but show large differences under practical conditions. Healthcare workers should not rely on results from suspension tests when deciding on a product for surgical hand disinfection.     

State-of-the-art hand hygiene in community medicine

Hand hygiene becomes more important in community medicine not only since antibiotic resistant bacteria such as MRSA spread within the community. Hands may be colonized with transient microorganism in up to 75%. Among those transient pathogens S. aureus, C. difficile or the hepatitis C virus may be found. During patient care the number of microorganisms on the hands steadily increases. In addition hands may be contaminated with different kinds of germs even if only “clean” activities are carried out. Gloves may be worn but do not provide complete protection from contamination due to leaks. Therefore hands should always be treated after gloves are taken off. State-of-the-art treatment of hands is the hygienic hand disinfection with alcohol-based hand rubs. They are more effective, quicker to carry out, better tolerated by the skin, with a positive effect on compliance, and cost effective in comparison to antiseptic soaps based on chlorhexidine or triclosan and in comparison to normal non-medicated soaps. Healthy skin easily tolerates alcohol-based products from the beginning on. Only health care workers with an underlying irritative contact dermatitis which is often caused by bar or liquid antiseptic soaps may have difficulties to use alcohol-based products initially. In such a case treatment of the underlying skin condition is the way to go and not staying with a preparation which has caused the dermatitis. All this knowledge is now reflected in current guidelines on hand hygiene. Beside liquids alcohol-based gels can be used if they have an antimicrobial activity equal to alcohol-based liquid preparations. Hand hygiene remains the single most important tool to avoid cross transmission of microorganisms between patients. This state-of-the-art hand hygiene should also be emphasized more in community medicine. This review may help to go the first step into this direction.     

Ethanol in pre-surgical hand rubs: concentration and duration of application for achieving European Norm EN 12791

In Europe, ethanol is a common active agent in hand rub formulations and nowadays it is also recommended in guidelines for hand hygiene published by the Centers for Disease Control and Prevention and by the World Health Organization. However, data on the range of concentrations and durations of application providing a basis for passing the efficacy test of the European norm EN 12791 are still lacking. Therefore, the bactericidal efficacy of rubbing clean hands with pure ethanol in volume concentrations of 95%, 85% or 75% during 3 min was compared with that of the reference procedure of EN 12791 employing n-propanol 60% v/v for 3 min, immediately and 3h after disinfection. Ethanol 85% was also tested at a 5 min application. A Latin-square design was used with 20 randomly allotted volunteers. Whereas the mean immediate bacterial reductions caused by ethanol at concentrations of 75% (log RF 1.68) and 95% (log RF 2.70) were significantly less efficacious compared to that of the reference (log RF 3.27), at 85% they were not significantly less active with both applications, 3 and 5 min (log RFs 2.90 and 3.12, respectively). Three hours after antisepsis, the bacterial reduction on the gloved hand was only significantly less efficacious than that of the reference when 75% ethanol was used. It is concluded that ethanol-based hand rubs have a good chance of meeting the EN 12791 requirements if their ethanol concentration is >75% v/v but <95% v/v and if they are applied for at least 3 min.     

European norms in hand hygiene

In the area of hand hygiene, European Norms exist, or are under development, with regard to protective gloves and for assessing the antimicrobial efficacy of hand disinfectants. Important norms for gloves are EN 420 (General requirements), EN 374 (Protective gloves against chemicals and microorganisms) and EN 455 (Medical gloves for single use). A suspension test for the demonstration of bactericidal activity (prEN 12054) is obligatory for hand disinfectants in all fields of application; a test to prove activity against yeasts applies only to hygienic hand rub. (Optional) Claims for virucidal activities can be substantiated by prEN 1476 and, in future, for mycobactericidal capacity by a test which is still under development. In vivo tests exist for post-contamination treatments, hygienic hand wash and hygienic hand rub (EN 1499 and EN 1500 respectively), and for the preoperative surgical hand rub/wash (prEN 12791). The two former tests employ artificially contaminated hands, the latter test is done with clean hands. All in vivo tests use reference hand treatments (with unmedicated soap or 2-propanol 60% (vol.) or 1-propanol 60% (vol.), respectively) against the results of which are compared with those achieved with the product under test and with the same volunteers. An antiseptic soap needs to be significantly more efficacious than unmedicated soap, a product for hygienic hand rub must not be inferior to the reference treatment with 2-propanol, and a surgical hand disinfectant must not cause a smaller bacterial reduction than the reference preparation with 1-propanol, immediately, and after 3 h. An (optional) claim for sustained activity of a surgical disinfectant needs to be demonstrated by achieving a significantly stronger bacterial reduction after 3 h than the reference preparation.     

World Health Organization-recommended hand-rub formulations do not meet European efficacy requirements for surgical hand disinfection in five minutes

The World Health Organization (WHO) has recommended two hand-rub formulations for local production based on 80% ethanol or 75% isopropanol (both v/v). We have looked at their efficacy according to EN 12791. Twenty-six subjects treated their hands with the reference procedure (n-propanol, 60%) for 3 min or with one of the two formulations for 1.5, 3 or 5 min (Latin square design). Post-values (immediate effect) were taken from one hand, the other hand was gloved for 3 h. After the glove had been taken off, the second post-value was taken (3 h effect). The mean log(10) reduction of each hand rub at all three application times was compared to Hodges and Lehmann's reference procedure for non-inferiority. In the first block the reference procedure reduced bacterial load by 2.43 log(10) (immediate effect) and 2.22 log(10) (3 h effect). The efficacy of the ethanol-based formulation (e.g. immediate efficacy of 1.41 log(10) at 5 min) was inferior to the reference procedure at all application times [lower 95% confidence interval (CI): less than -0.75]. In the second block the reference procedure reduced bacterial load by 2.72 log(10) (immediate effect) and 2.26 log(10) (3 h effect). The efficacy of the isopropanol-based formulation (e.g. immediate efficacy of 2.05 log(10) at 5 min) was also inferior to the reference procedure at all application times (lower 95% CI: less than -0.75). Both WHO-recommended hand-rub formulations failed to meet the EN 12791 efficacy requirements for surgical hand disinfection within 5 min. A higher concentration of the active ingredients may improve the efficacy.     

Comparative review of the test design Tentative Final Monograph (TFM) and EN 12791 for surgical hand disinfectants

Preoperative antiseptic treatment of the hands of the surgical team is a standard procedure used worldwide in order to reduce the risk of surgical site infection. Two different types of antiseptics are available: alcohol-based hand rubs and antimicrobial liquid detergents ("soaps"). Standards have been developed to determine the antimicrobial efficacy of such preparations: the European norm EN 12971, finally issued in 2005, and the Tentative Final Monograph (TFM) for health care antiseptic products from 1994, which is the corresponding document in the USA. Although both methods use the reduction of resident hand flora as a quantitative parameter for antimicrobial efficacy, there are major differences concerning the test design. Whereas the European method is carried out following a randomized, reference-controlled crossover design, the US method can be characterized as a randomized, blinded parallel arm design. While both standards aim at immediate as well as sustained efficacy of the procedure, according to the EN the test product must not be significantly less effective than the reference procedure, whereas the TFM requires absolute reduction of > or = 1, > or = 2, and > or = 3 log10 per hand on days 1, 2, and 5, respectively. Results from various studies demonstrated that meeting the criteria defined by both standards may happen, but meeting the specifications of one standard does not necessarily mean that the same product will pass the requirements of the other. Missing accordance may be due to a number of considerable differences between both test methods. For a number of reasons the European method seems to be closer to clinical practice and to provide higher patient safety than the US method. However, available study data do neither allow for evaluation of the clinical impact of surgical hand disinfection as such nor of the effect of a particular product on postoperative wound infection rates.     

Introducing alcohol-based hand rub for hand hygiene: the critical need for training.

BACKGROUND: Use of an alcohol-based hand rub for hand hygiene has recently been recommended by the Centers for Disease Control and Prevention. However, the proper technique for using hand rub has not been well described and is not routinely taught in hospitals. OBJECTIVE: To evaluate the impact of training on proper technique as outlined by the European Standard for testing alcohol-based hand rubs (European Norm 1500) in a clinical study. DESIGN, SETTING, AND PATIENTS: Prospective study including 180 healthcare workers (HCWs) in a 450-bed, university-affiliated geriatric hospital where alcohol-based hand rub was introduced in the late 1970s. INTERVENTION: Structured training program in hand hygiene with alcohol-based hand rub. Technique for using hand rub was tested by the addition of a fluorescent dye to the disinfectant and the number of areas missed was quantified by a validated visual assessment method. In addition, the number of bacteria eradicated was estimated by calculating the difference between the log(10) number of colony-forming units (cfu) of bacteria on the fingertips before and after the procedure, and reported as reduction factor (RF). MAIN OUTCOME MEASURE: Log(10) cfu bacterial counts on fingertips before and after training in the appropriate technique for using hand rub. RESULTS: At baseline, only 31% of HCWs used proper technique, yielding a low RF of 1.4 log(10) cfu bacterial count. Training improved HCW compliance to 74% and increased the RF to 2.2 log(10) cfu bacterial count, an increase of almost 50% (P<.001). Several factors, such as applying the proper amount of hand rub, were significantly associated with the increased RF. CONCLUSION: These results demonstrate that education on the proper technique for using hand rub, as outlined in EN 1500, can significantly increase the degree of bacterial killing.     

Adoption of alcohol hand disinfection in the United States: a personal perspective

Even though alcohol-based hand disinfectants have been used for decades as a routine measure in Europe, in the USA until recently handwashing was the procedure of choice. Alcohol-based rub products were recommended only if no handwashing facility or running water was available. It was only during the late 80s and early 90s that the advantages of alcohol-based products began to elicit interest. In 1995 Larsen published new application guidelines for hand disinfection and in 1996 the CDC included alcohol-based hand disinfection in its “Isolation guideline”. However, these recommendations were rarely implemented in practice. In 1996 Didier Pittet first gave me a demonstration of alcohol-based rub products at his Geneva hospital, and the following year experts at Lausanne University provided me with the products available at that time. In 1998 and 2000 I had the opportunity to exchange information and experiences with numerous European experts, including Dr. Molitor, who also gave me additional insights into the mechanism of action of such products. As a result of myriad scientific demonstrations, interest in these rub products now began to be expressed in the USA too. In 1999 an interdisciplinary working group for hand hygiene was set up, comprising representatives from CDC’s Healthcare Infection Control Practices Advisory Committee (HICPAC), the Society for Healthcare Epidemiology of America, the Association for Professionals in Infection Control and the Infectious Diseases Society of America, whose intention was to formulate new guidelines for hand hygiene in the healthcare sector. The insights that I gained from Dr. Molitor and from other European experts were of enormous value and helped to weigh up the pros and cons of alcohol-based hand disinfection, both in respect of the different products available and on comparing them with hand washing. The new CDC guideline for hand hygiene was published in 20002 and for the first time in the USA it featured the requirement that alcohol-based rub products be used as the method of choice provided that the hands were not visibly soiled or contaminated with protein-based material. Unfortunately, we have no reliable data, but it is estimated that today up to 95% of doctors and nurses in American hospitals preferentially use alcohol-based rub products – thus reflecting a situation that has long been common practice in Europe.