Antimicrobial efficacy of alcohol-based hand gels

Virulence factors, antifungal susceptibility and molecular profile in Candida species isolated from the hands of health professionals before and after cleaning with 70% ethyl alcohol-based gel

Fungal infections in neonatal intensive care units (NICU) are mainly related to Candida species, with high mortality rates. They are predominantly of endogenous origin, however, cross-infection transmitted by healthcare professionals' hands has occurred. The aim of this study was to identify Candida species isolated from the hands of healthcare professionals in a NICU before and after hygiene with 70% ethanol-based gel and evaluate virulence factors DNase, phospholipase, proteinase, hemolysin, biofilm biomass production, and metabolic activity. In vitro antifungal susceptibility testing and similarity by random amplified polymorphic DNA (RAPD) were also performed. C. parapsilosis complex was the most frequent species (57.1%); all isolates presented at least one virulence factor; three isolates (Candida parapsilosis complex) were resistant to amphotericin B, two (Candida famata [currently Debaryomyces hansenii] and Candida guilliermondii [currently Meyerozyma guilliermondii]) was resistant to micafungin, and six (Candida parapsilosis complex, Candida guilliermondii [=Meyerozyma guilliermondii], Candida viswanathi, Candida catenulata [currently Diutina catenulata] and Candida lusitaniae [currently Clavispora lusitaniae]) were resistant to fluconazole. Molecular analysis by RAPD revealed two clusters of identical strains that were in the hands of distinct professionals. Candida spp. were isolated even after hygiene with 70% ethanol-based gel, highlighting the importance of stricter basic measures for hospital infection control to prevent nosocomial transmission.

Hand Sanitizer Gels: Classification, Challenges, and the Future of Multipurpose Hand Hygiene Products

Hand hygiene is a crucial measure in the prevention and control of infections, and there is a growing awareness among individuals who are making a conscious effort to maintain hand cleanliness. With the advent of the SARS-CoV-2 outbreak, the demand for hand hygiene products has also gradually shifted towards those with antimicrobial properties. Among these products, hand sanitizer gels (HSGs) have gained considerable popularity as an efficient method of hand cleaning, due to their rapid drying and sustained antimicrobial efficacy. Concurrently, there has been a growing interest in novel HSGs that offer additional functions such as skin whitening, moisturizing, and anti-inflammatory effects. These novel HSGs effectively address concerns associated with the ingestion of antimicrobial ingredients and demonstrate reduced skin irritation, thereby alleviating hand dermatological issues. This review provides an extensive overview of the application scenarios, classification, and challenges associated with HSGs while emphasizing the emergence of novel components with biological functions, aiming to contribute to the advancement of hand hygiene practices and offer novel insights for the development of novel HSGs with outstanding antimicrobial properties with other multiple biological functions and desirable biosafety profiles.

Evidence-based hand hygiene: Liquid or gel handrub, does it matter?

BACKGROUND

Recent studies put under scrutiny the prevailing hand hygiene guidelines, which incorporate quantitative parameters regarding handrub volume and hand size. Understanding the criticality of complete (i.e., efficient) hand hygiene in healthcare, objectivization of hand hygiene related parameters are paramount, including the formulation of the ABHR. Complete coverage can be achieved with optimal Alcohol-Based Hand Rub (ABHR) provided. The literature is limited regarding ABHR formulation variances to antimicrobial efficiency and healthcare workers' preference, while public data on clinically relevant typical application differences is not available. This study was designed and performed to compare gel and liquid format ABHRs (the two most popular types in Europe) by measuring several parameters, including application time, spillage and coverage.

METHODOLOGY

Senior medical students were invited, and randomly assigned to receive pre-determined ABHR volumes (1.5 or 3 ml). All the 340 participants were given equal amounts of gel and liquid on two separate hand hygiene occasions, which occurred two weeks apart. During the hand hygiene events, by employing a digital, fully automated system paired with fluorescent-traced ABHRs, disinfectant hand coverage was objectively investigated. Furthermore, hand coverage in relation to the participants' hand sizes was also calculated. Additional data collection was performed regarding volume differences and their effect on application time, participants' volume awareness (consciousness) and disinfectant spillage during the hand hygiene events.

RESULTS

The 1.5 ml ABHR volume (commonly applied in healthcare settings) is insufficient in either formulation, as the non-covered areas exceeded significant (5%+) of the total hand surface area. 3 ml, on the contrary, resulted in almost complete coverage (uncovered areas remained below 1.5%). Participants typically underestimated the volume which they needed to apply. While the liquid ABHR spreads better in the lower, 1.5 ml volume compared to the gel, the latter was easier handled at larger volume. Drying times were 30/32 s (gel and liquid formats, respectively) when 1.5 ml handrub was applied, and 40/42 s when 3 ml was used. As the evaporation rates of the ABHR used in the study are similar to those available on the market, one can presume that the results presented in the study apply for most WHO conform ABHRs.

CONCLUSION

The results show that applying 1.5 ml volume was insufficient, as large part of the hand surface remained uncovered (7.0 ± 0.7% and 5.8 ± 1.0% of the hand surface in the case of gel and liquid, respectively) When 3 ml handrub was applied drying times were 40 and 42 s (gel and liquid, respectively), which is a very long time in daily clinical practice. It looks like we cannot find a volume that fits for everyone. Personalized, hand size based ABHR volumes may be the solution to find an optimal balance between maximize coverage and minimise spillage and drying time. 3 ml can be a good volume for those who have medium size hands. Large handed people should use more handrub to reach appropriate coverage, while small-handed ones may apply less to avoid massive spillage and not to take unrealistically long to dry.

Improvement of hand hygiene adherence among staff in long-term care facilities for elderly in Japan

INTRODUCTION

Hand hygiene is crucial for infection control in long-term care facilities for elderly (LTCFEs), because it can be easily implemented in the low-resource settings of LTCFEs. This study investigated the actual status of hand hygiene adherence in LTCFEs, identified the factors inhibiting its appropriate implementation, and evaluated the effectiveness of a hand hygiene promotion program.

METHODS

In this before-and-after study, participants were staff members (n = 142) at two LTCFEs in Gunma Prefecture, Japan. We modified the World Health Organization's "five moments for hand hygiene" and assessed participants' hand hygiene adherence rates in four situations: (1) Before touching around a resident's mucous membrane area; (2) Before medical practice or clean/aseptic procedures; (3) After body fluid exposure/risk or after touching around a resident's mucous membrane area; and (4) After touching a resident's contaminated environments. The study was divided into four phases. In Phase 1, participants self-assessed their hand hygiene adherence using a questionnaire. In Phase 2, we objectively assessed participants' pre-intervention adherence rates. In Phase 3, an intervention comprising various hand hygiene promotion measures, such as education and hands-on training on hand hygiene practices and timings, was implemented. In Phase 4, participants' post-intervention adherence rates were objectively measured.

RESULTS

Although most participants reported high hand hygiene adherence rate in the self-assessment (93.1%), the pre-intervention evaluation revealed otherwise (16.8%). Participants' post-intervention adherence rates increased for all four situations (77.3%).

CONCLUSION

The intervention program helped increase participants' hand hygiene adherence rates, indicating its effectiveness. Similar interventions in other LTCFEs may also improve adherence rates.

Handrubbing with sprayed alcohol-based hand rub: an alternative method for effective hand hygiene

BACKGROUND

Hand hygiene is crucial in infection prevention and control. It is unclear whether sprayed alcohol-based hand rub (ABHR) is non-inferior to the World Health Organization (WHO)-recommended method of handrubbing with poured ABHR.

AIM

To test whether sprayed ABHR can be an alternative (non-inferior) method for effective hand hygiene with/without handrubbing.

METHODS

A laboratory experiment was conducted with ABHR (isopropanol 60% v/v) according to European Norm 1500. Hand hygiene was performed by: (1) handrubbing with ABHR poured on to the palm of the hand; (2) handrubbing with sprayed ABHR; and (3) applying sprayed ABHR to hands without handrubbing. Hands were contaminated with Escherichia coli ATCC 10536, followed by hand hygiene and microbiological sampling. A generalized linear mixed model with a random intercept per subject was used to analyse the reduction in bacterial count following hand hygiene.

FINDINGS

In total, 19 healthcare workers participated in the study. Handrubbing with sprayed ABHR was non-inferior [margin log₁₀ 0.6 colony-forming units (cfu)/mL] to the WHO-recommended method of handrubbing with poured ABHR; bacterial count reductions were log₁₀ 3.66 cfu/mL [95% confidence interval (CI) 1.68-5.64] and log₁₀ 3.46 cfu/mL (95% CI 1.27-5.65), respectively. Conversely, non-inferiority was not found for sprayed ABHR without handrubbing [bacterial count reduction log₁₀ 2.76 cfu/mL (95% CI 1.65-3.87)].

CONCLUSION

Handrubbing with sprayed ABHR was non-inferior to handrubbing with ABHR poured on to the palm of the hand to reduce bacterial counts on hands under experimental conditions. Handrubbing with sprayed ABHR may be an acceptable alternative hand hygiene method pending assessment in other settings and for other pathogens.

Quantifying the Effects of Water Temperature, Soap Volume, Lather Time, and Antimicrobial Soap as Variables in the Removal of Escherichia coli ATCC 11229 from Hands

The literature on hand washing, while extensive, often contains conflicting data, and key variables are only superficially studied or not studied at all. Some hand washing recommendations are made without scientific support, and agreement between recommendations is limited. The influence of key variables such as soap volume, lather time, water temperature, and product formulation on hand washing efficacy was investigated in the present study. Baseline conditions were 1 mL of a bland (nonantimicrobial) soap, a 5-s lather time, and 38°C (100°F) water temperature. A nonpathogenic strain of Escherichia coli (ATCC 11229) was the challenge microorganism. Twenty volunteers (10 men and 10 women) participated in the study, and each test condition had 20 replicates. An antimicrobial soap formulation (1% chloroxylenol) was not significantly more effective than the bland soap for removing E. coli under a variety of test conditions. Overall, the mean reduction was 1.94 log CFU (range, 1.83 to 2.10 log CFU) with the antimicrobial soap and 2.22 log CFU (range, 1.91 to 2.54 log CFU) with the bland soap. Overall, lather time significantly influenced efficacy in one scenario, in which a 0.5-log greater reduction was observed after 20 s with bland soap compared with the baseline wash (P = 0.020). Water temperature as high as 38°C (100°F) and as low as 15°C (60°F) did not have a significant effect on the reduction of bacteria during hand washing; however, the energy usage differed between these temperatures. No significant differences were observed in mean log reductions experienced by men and women (both 2.08 log CFU; P = 0.988). A large part of the variability in the data was associated with the behaviors of the volunteers. Understanding what behaviors and human factors most influence hand washing may help researchers find techniques to optimize the effectiveness of hand washing.

Contamination of healthcare workers' hands with bacterial spores

Clostridium species and Bacillus spp. are spore-forming bacteria that cause hospital infections. The spores from these bacteria are transmitted from patient to patient via healthcare workers' hands. Although alcohol-based hand rubbing is an important hand hygiene practice, it is ineffective against bacterial spores. Therefore, healthcare workers should wash their hands with soap when they are contaminated with spores. However, the extent of health care worker hand contamination remains unclear. The aim of this study is to determine the level of bacterial spore contamination on healthcare workers' hands. The hands of 71 healthcare workers were evaluated for bacterial spore contamination. Spores attached to subject's hands were quantitatively examined after 9 working hours. The relationship between bacterial spore contamination and hand hygiene behaviors was also analyzed. Bacterial spores were detected on the hands of 54 subjects (76.1%). The mean number of spores detected was 468.3 CFU/hand (maximum: 3300 CFU/hand). Thirty-seven (52.1%) and 36 (50.7%) subjects were contaminated with Bacillus subtilis and Bacillus cereus, respectively. Nineteen subjects (26.8%) were contaminated with both Bacillus species. Clostridium difficile was detected on only one subject's hands. There was a significant negative correlation between the hand contamination level and the frequency of handwashing (r = -0.44, P < 0.01) and a significant positive correlation between the hand contamination level and the elapsed time since last handwashing (r = 0.34, P < 0.01). Healthcare workers' hands may be frequently contaminated with bacterial spores due to insufficient handwashing during daily patient care.

A step-wise approach towards introduction of an alcohol based hand rub, and implementation of front line ownership- using a, rural, tertiary care hospital in central India as a model

BACKGROUND

Appropriate hand hygiene is a gold standard to combat healthcare associated infections (HAIs). The World Health Organization (WHO) has recommended alcohol based hand rub (ABHR) as the most effective tool to maintain hand hygiene. In resource poor settings commercially available ABHR is not "economically accessible". The objectives of this study were to assess the acceptability of, and to build confidence for an in-house prepared (based on WHO guidelines) alcohol based hand rub among healthcare workers (HCWs) using a rural, tertiary care hospital in central India as an example.

METHODS

A series of activities were developed and conducted based on the Precede-Proceed model, the Trans Theoretical model of behaviour change, Front line ownership and Social marketing. A modified WHO-ABHR formulation, the 'test product' and 'WHO product evaluation form' were used for self assessment of acceptability of the 'test product'. Confidence building activities, as finger tip culture, visual portrayal method and handmade posters, were used in high-risk wards for HAIs, to build confidence for the 'test product' in removing transient flora from the hands. A locally developed feedback from was used to evaluate the impact of the activities conducted.

RESULTS

Overall 183 HCWs were enrolled for the assessment of the 'test product' (130- doctors and 53 nurses). Out of these 83% (108/130) doctors and 94% (50/53) nurses were satisfied with the 'test product'. The confidence building activity was conducted with 116 participants (49 doctors). After single use of the 'test product', overall a significant reduction was observed for the CFUs on the blood agar plates (0.77 Log(10), p < 0.001). A complete reduction (100%) in colony forming units on incubated blood agar plates was seen for 13% (15/116) participants. Eighty two percent (95/116) participants expressed their confidence in the 'test product'.

CONCLUSION

The self reported acceptance level for the 'test product' was high. The use of finger tip culture coupled with the visual portrayal was perceived as a convincing and highly effective way to develop confidence in HCWs. Thus, is the foremost step towards successful introduction of ABHR and can be seen as a model for similar settings.

Cold atmospheric pressure plasma and decontamination. Can it contribute to preventing hospital-acquired infections?

Healthcare-associated infections (HCAIs) affect ∼4.5 million patients in Europe alone annually. With the ever-increasing number of 'multi-resistant' micro-organisms, alternative and more effective methods of environmental decontamination are being sought as an important component of infection prevention and control. One of these is the use of cold atmospheric pressure plasma (CAPP) systems with clinical applications in healthcare facilities. CAPPs have been shown to demonstrate antimicrobial, antifungal and antiviral properties and have been adopted for other uses in clinical medicine over the past decade. CAPPs vary in their physical and chemical nature depending on the plasma-generating mechanism (e.g. plasma jet, dielectric barrier discharge, etc.). CAPP systems produce a 'cocktail' of species including positive and negative ions, reactive atoms and molecules (e.g. atomic oxygen, ozone, superoxide and oxides of nitrogen), intense electric fields, and ultraviolet radiation (UV). The effects of these ions have been studied on micro-organisms, skin, blood, and DNA; thus, a range of possible applications of CAPPs has been identified, including surface decontamination, wound healing, biofilm removal, and even cancer therapy. Here we evaluate plasma devices, their applications, mode of action and their potential role specifically in combating HCAIs on clinical surfaces.

[Comparison of antimicrobial effect of alcohol gel according to the amount and drying time in health personnel hand hygiene]

PURPOSE

The purpose of this study was to compare the effect of alcohol gel according to the amount and drying time in health personnel hand hygiene and to promote in their practice adequate and effective hand hygiene.

METHODS

The cross-over experimental study was performed with 14 volunteers. Hands were artificially contaminated with 5 mL of 10⁸ CFU/mL of Serratia marcescens (ATCC 14756) and four different alcohol gel hand hygiene methods varying by the amount of alcohol gel (2 mL vs. 1 mL) and drying time (complete vs. incomplete) were compared. Samples were collected by glove juice sampling procedures.

RESULTS

Mean log reduction values of the four different hand hygiene methods were 2.22±0.36, 1.26±0.53, 1.49±0.60, 0.89±0.47 respectively for the 4 groups: adequate amount (2mL) and complete dry (30 seconds rubbing followed by 2 min air-dry), inadequate amount (1 mL) and complete dry, adequate amount and incomplete dry (15 seconds rubbing and no air-dry), and inadequate amount and incomplete dry. The difference was statistically significant in the adequate amount and complete dry group compared to other three groups (p<.001).

CONCLUSION

Only alcohol gel hand hygiene with adequate amount and complete drying was satisfactory by U.S. FDA-TFM efficacy requirements for antiseptic hand hygiene products.

The uses and abuses of rapid bioluminescence-based ATP assays

Bioluminescence-based ATP testing of solid surfaces has become well established in the food processing industry as part of general hazard analysis and critical control points (HACCP) measures. The rise in healthcare associated infections (HAIs) at the turn of the century focussed attention on the environment as a potential reservoir of the agents responsible for such infections. In response to the need for objective methods of assessing the efficiency of cleaning in healthcare establishments and for rapid methods for detecting the presence of the pathogens responsible for HAIs, it was proposed that ATP testing of environmental surfaces be introduced. We examine the basis behind the assumptions inherent in these proposals. Intracellular ATP levels are shown to vary between microbial taxa and according to environmental conditions. Good correlations between microbial numbers and ATP levels have been obtained under certain specific conditions, but never within healthcare settings. Notwithstanding, ATP testing may still have a role in providing reassurance that cleaning regimes are being carried out satisfactorily. However, ATP results should not be interpreted as surrogate indicators for the presence of microbial pathogens.

Back to the future: rising to the Semmelweis challenge in hand hygiene

Hand hygiene is the single most important intervention for reducing healthcare associated infections and preventing the spread of antimicrobial resistance. This sentence begins most publications regarding hand hygiene in the medical literature. But why - as we mark 150 years since the publication of Ignaz Semmelweis' landmark monograph on the subject - do we continue to repeat it? One might be tempted to regard it as a truism. However, while tremendous progress has certainly been made in this field, a significant amount of work is yet to be done in both strengthening the evidence regarding the impact of hand hygiene and maximizing its implementation. Hand hygiene cannot yet be taken for granted. This article summarizes historical perspectives, dynamics of microbial colonization and efficacy of hand cleansing methods and agents, elements and impacts of successful hand hygiene promotion, as well as scale-up and sustainability. We also explore hand hygiene myths and current challenges such as monitoring, behavior change, patient participation and research priorities.