Handwashing and disinfection of heavily contaminated hands—effective or ineffective?

Infection control measures to stop the spread of sequence type 15 OXA-23-producing Acinetobacter baumannii in a Swedish Burn Center

OBJECTIVE

To describe the course of the outbreak and infection control measures to stop the spread of sequence type 15 OXA-23-producing Acinetobacter baumannii in the Burn Center of Uppsala University Hospital, between November 2014 and the end of April 2015.

METHODS

Compliance with hand hygiene, dress code, and cleaning routines were reviewed, the ward's environment was systematically investigated to identify potential environmental sources. Sampling routines for A. baumannii, from patients and environment, were established, and the epidemiological relationship was analysed for all carbapenem-resistant A. baumannii isolates using arbitrarily primed polymerase chain reaction (AP-PCR) and pulsed-field gel electrophoresis (PFGE).

RESULTS

A total of 54 patients were treated at the burn intensive care unit during the studied, approximately five months period, and an OXA-23-producing A. baumannii was isolated from nine patients (9/54, 17%), whereof two died (2/9, 22.2%). All isolates shared identical PFGE-genotype patterns and belonged to sequence type 15; AP-PCR was eligible for prompt epidemiological investigations.

CONCLUSIONS

Higher awareness and increased compliance with hand hygiene and dress code as well as intensified cleaning protocols of the environment and equipment were successfully established and likely to have led to stop the spread of sequence type 15 OXA-23-producing Acinetobacter baumannii.

Epidermis as a Platform for Bacterial Transmission

The epidermis constitutes a continuous external layer covering the body, offering protection against bacteria, the most abundant living organisms that come into contact with this barrier. The epidermis is heavily colonized by commensal bacterial organisms that help protect against pathogenic bacteria. The highly regulated and dynamic interaction between the epidermis and commensals involves the host’s production of nutritional factors promoting bacterial growth together to chemical and immunological bacterial inhibitors. Signal trafficking ensures the system’s homeostasis; conditions that favor colonization by pathogens frequently foster commensal growth, thereby increasing the bacterial population size and inducing the skin’s antibacterial response, eliminating the pathogens and re-establishing the normal density of commensals. The microecological conditions of the epidermis favors Gram-positive organisms and are unsuitable for long-term Gram-negative colonization. However, the epidermis acts as the most important host-to-host transmission platform for bacteria, including those that colonize human mucous membranes. Bacteria are frequently shared by relatives, partners, and coworkers. The epidermal bacterial transmission platform of healthcare workers and visitors can contaminate hospitalized patients, eventually contributing to cross-infections. Epidermal transmission occurs mostly via the hands and particularly through fingers. The three-dimensional physical structure of the epidermis, particularly the fingertips, which have frictional ridges, multiplies the possibilities for bacterial adhesion and release. Research into the biology of bacterial transmission via the hands is still in its infancy; however, tribology, the science of interacting surfaces in relative motion, including friction, wear and lubrication, will certainly be an important part of it. Experiments on finger-to-finger transmission of microorganisms have shown significant interindividual differences in the ability to transmit microorganisms, presumably due to genetics, age, sex, and the gland density, which determines the physical, chemical, adhesive, nutritional, and immunological status of the epidermal surface. These studies are needed to optimize interventions and strategies for preventing the hand transmission of microorganisms.

A 3D-printed, touch-activated, sanitizer dispensing device for reducing healthcare-acquired infections

Aim: We present a touch-activated, sanitizer dispensing (TSD) device, intended to be mounted on high-touch surfaces, that aims to reduce nosocomial infections. It disinfects the person’s hand touching its surface while being self-sterilizing. Materials & methods: The TSD device consists of an array of 3D-printed, passive, miniaturized, mechanical valves that dispense a small amount of liquid sanitizer when touched. Its mechanical performance and disinfecting efficiency were quantified using simulations and experimental tests. Results & conclusion: The TSD device has a disinfecting efficiency comparable to the standard hand sanitizing approach, reducing the microbiological load by approximately 30-times. It can be easily mounted on high-touch surfaces in a healthcare setting and it is expected to greatly reduce the spread of nosocomial infections.

Impact of Alcohol-Based, Waterless Hand Antiseptic on the Incidence of Infection and Colonization With Methicillin-Resistant Staphylococcus aureus and Vancomycin-Resistant Enterococci

Objective:

Colonized and infected inpatients are major reservoirs for methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE), and transient carriage of these pathogens on the hands of healthcare workers remains the most common mechanism of patient-to-patient transmission. We hypothesized that use of alcohol-based, waterless hand antiseptic would lower the incidence of colonization and/or infection with MRSA and VRE.

Methods.

On June 19, 2001, alcohol hand antiseptic was introduced at the University campus and not the nearby Memorial campus of the University of Massachusetts Medical School (Worcester, MA), allowing us to evaluate the impact of this antiseptic on the incidence of MRSA and VRE colonization and infection. From January 1 through December 31, 2001, the incidence of MRSA colonization or infection was compared between the 2 campuses before and after the hand antiseptic was introduced. Its effect on VRE colonization and infection was only studied in the medical intensive care unit at the University campus.

Results.

At the University campus, the incidence of MRSA colonization or infection decreased from 1.26 cases/1,000 patient-days before the intervention to 0.75 cases/1,000 patient-days after the intervention, for a 1.46-fold decrease (95% confidence interval, 1.04-2.58; P = .037). At the Memorial campus, the incidence of MRSA colonization or infection remained virtually unchanged, from 0.34 cases/1,000 patient-days to 0.49 cases/1,000 patient-days during the same period. However, a separate analysis of the University campus data that controlled for proximity to prevalent cases did not show a significant improvement in the rates of infection or colonization. The incidence of nosocomial VRE colonization or infection before and after the hand antiseptic decreased from 12.0 cases/1,000 patient-days to 3.0 cases/1,000 patient-days, a 2.25-fold decrease (P = .018). Compliance with rectal surveillance for detection of VRE was 86% before and 84% after implementation of the hand antiseptic intervention. The prevalences of VRE cases during these 2 periods were 25% and 29%, respectively (P = .017).

Conclusions.

Alcohol hand antiseptic appears to be effective in controlling the transmission of VRE. However, after controlling for proximity to prevalent cases (ie, for clustering), it does not appear to be more effective than standard methods for controlling MRSA. Further controlled studies are needed to evaluate its effectiveness.

Individual variability in finger-to-finger transmission efficiency of Enterococcus faecium clones

A fingertip-to-fingertip intraindividual transmission experiment was carried out in 30 healthy volunteers, using four MLST-typed Enterococcus faecium clones. Overall results showed an adequate fit goodness to a theoretical exponential model, whereas four volunteers (13%) exhibited a significantly higher finger-to-finger bacterial transmission efficiency. This observation might have deep consequences in nosocomial epidemiology.

A meta-analysis of the published literature on the effectiveness of antimicrobial soaps

The goal of this research was to conduct a systematic quantitative analysis of the existing data in the literature in order to determine if there is a difference between antimicrobial and nonantimicrobial soaps and to identify the methodological factors that might affect this difference. Data on hand washing efficacy and experimental conditions (sample size, wash duration, soap quantity, challenge organism, inoculum size, and neutralization method) from published studies were compiled and transferred to a relational database. A total of 25 publications, containing 374 observations, met the study selection criteria. The majority of the studies included fewer than 15 observations with each treatment and included a direct comparison between nonantimicrobial soap and antimicrobial soap. Although differences in efficacy between antimicrobial and nonantimicrobial soap were small (∼0.5-log CFU reduction difference), antimicrobial soap produced consistently statistically significantly greater reductions. This difference was true for any of the antimicrobial compounds investigated where n was >20 (chlorhexidine gluconate, iodophor, triclosan, or povidone). Average log reductions were statistically significantly greater (∼2 log CFU) when either gram-positive or gram-negative transient organisms were deliberately added to hands compared with experiments done with resident hand flora (∼0.5 log CFU). Our findings support the importance of using a high initial inoculum on the hands, well above the detection limit. The inherent variability in hand washing seen in the published literature underscores the importance of using a sufficiently large sample size to detect differences when they occur.

Decreasing central line associated bloodstream infection in neonatal intensive care

Central Line Associated Bloodstream Infections (CLABSIs) have come to be recognized as preventable adverse events that result from lapses in technique at multiple levels of care. CLABSIs are associated with increased mortality and adverse outcomes that may have lifelong consequences. This review provides a summary of evidence-based strategies to reduce CLABSI in the newborn intensive care unit that have been described in the literature over the past decades. Implementation of these strategies in "bundles" is also discussed, citing examples of successful quality improvement collaboratives. The methods of implementation require an understanding of the scientific data and technical developments, as well as knowledge of how to influence change within the unique and complicated milieu of the newborn intensive care unit.

Impact of enhanced infection control at 2 neonatal intensive care units in the Philippines

BACKGROUND

The growing burden of neonatal mortality associated with hospital-acquired neonatal sepsis in the developing world creates an urgent need for cost-effective infection-control measures in resource-limited settings.

METHODS

Using a before-and-after comparison design, we measured how rates of staff hand-hygiene compliance, colonization with drug-resistant pathogens (defined as ceftazidime- and/or gentamicin-resistant gram-negative bacilli and drug-resistant gram-positive cocci), bacteremia, and overall mortality changed after the introduction of a simplified package of infection-control measures at 2 neonatal intensive care units (NICUs) in Manila, The Philippines.

RESULTS

Of all 1827 neonates admitted to the NICU, 561 (30.7%) arrived from delivery already colonized with drug-resistant bacteria. Of the 1266 neonates who were not already colonized, 578 (45.6%) became newly colonized with drug-resistant bacteria. Of all 1827 neonates, 358 (19.6%) became bacteremic (78.2% were infected with gram-negative bacilli) and 615 (33.7%) died. Of 2903 identified drug-resistant colonizing bacteria, 85% were drug-resistant gram-negative bacilli (predominantly Klebsiella species, Pseudomonas species, and Acinetobacter species) and 14% were methicillin-resistant Staphylococcus aureus. Contrasting the control period with the intervention period at each NICU revealed that staff hand-hygiene compliance improved (NICU 1: relative risk, 1.3; 95% confidence interval 1.1-1.5; NICU 2: relative risk, 1.6; 95% confidence interval, 1.4-2.0) and that overall mortality decreased (NICU 1: relative risk, 0.5; 95% confidence interval, 0.4-0.6; NICU 2: relative risk, 0.8; 95% confidence interval, 0.7-0.9). However, rates of colonization with drug-resistant pathogens and of sepsis did not change significantly at either NICU.

DISCUSSION

Nosocomial transmission of drug-resistant pathogens was intense at these 2 NICUs in The Philippines; transmission involved mostly drug-resistant gram-negative bacilli. Infection-control interventions are feasible and are possibly effective in resource-limited hospital settings.

Compliance with hand hygiene in a genitourinary medicine department

The ability to control hospital-acquired infections is highly dependent upon control of cross-contamination from health-care workers to patients, and from one anatomical area of the patient to another anatomical area. Hand hygiene has been demonstrated to be an essential prerequisite in preventing cross-contamination. Wearing gloves does not afford complete protection against cross-contamination. Hand hygiene includes handwashing between patients, the use of alcohol-based skin cleansers and changing or removing gloves between examining different anatomical sites. There are no previously published audits regarding compliance to hand hygiene in genitourinary (GU) medicine clinics. A validated observation tool was employed in this audit. Doctors and nurses were observed in clinical practice. The adherence to hand hygiene protocols was overall poor. Doctors were more likely to adhere to protocols than nurses (83.3% vs. 66%). However, techniques of glove removal were universally satisfactory. Strategies for improvement in hand hygiene are suggested. These include performance feedback and use of posters.

[Evaluation of a waterless, scrubless chlorhexidine gluconate/ethanol surgical scrub and povidone-iodine for antimicrobial efficacy]

PURPOSE

The purpose of this study was to compare 1% chlorhexidine-gluconate/61% ethanol (CHG/Ethanol) emollient and 7.5% povidone-iodine (PVI) scrub for antimicrobial,residual effect, and skin condition.

METHOD

CHG/Ethanol emollient hand hygiene was performed waterless, and brushless by operating doctors and nurses (N=20). PVI hand washing was performed with water and a brush (N=20) for 5 min. The subjects were asked to press their left hand in hand-shaped agar before a surgical scrub, immediately after a surgical scrub and after the operation. The amount of isolated microorganisms were calculated by counting the number of divided areas(1 x 1 cm, 160 cell) which were culture positive in the hand culture plate. The skin condition was evaluated.

RESULT

The antimicrobial count of CHG/Ethanol emollient and PVI immediately post surgical scrub was 0.0 vs. 4.1 (p>.05), and after the operation was 0.1 vs. 37.8 (p>.05)respectively. The Residual effect of CHG/Ethanol emollient immediately post surgical scrub and after the operation were 0.0 vs. 0.1 (p>.05), and PVI were 4.1 vs. 37.8 (p>.05)respectively. The skin condition and satisfaction of CHG/Ethanol emollient was higher than PVI (p<.05).

CONCLUSION

The antimicrobial effect between CHG/Ethanol emollient and PVI were the same. Considering skin condition, satisfaction and allergic reaction CHG/Ethanol emollient for surgical scrub is recommended in Korea.

Guidelines for the control of glycopeptide-resistant enterococci in hospitals

The increase since the mid 1980s in glycopeptide resistant enterococci (GRE) raised concerns about the limited options for antimicrobial therapy, the implications for ever-increasing numbers of immunocompromised hospitalised patients, and fuelled fears, now realised, for the transfer of glycopeptide resistance to more pathogenic bacteria, such as Staphylococcus aureus. These issues underlined the need for guidelines for the emergence and control of GRE in the hospital setting. This Hospital Infection Society (HIS) and Infection Control Nurses Association (ICNA) working party report reviews the literature relating to GRE prevention and control. It provides guidance on microbiological investigation, treatment and management, including antimicrobial prescribing and infection control measures. Evidence identified to support recommendations has been categorized. A risk assessment approach is recommended and areas for research and development identified.

Hand hygiene: simple and complex

This review gives an overview of hand hygiene in healthcare and in the community, including some aspects which have attracted little attention, such as hand drying and cultural issues determining hand hygiene behaviour. Hand hygiene is the most effective measure for interrupting the transmission of microorganisms which cause infection both in the community and in the healthcare setting. Using hand hygiene as a sole measure to reduce infection is unlikely to be successful when other factors in infection control, such as environmental hygiene, crowding, staffing levels and education are inadequate. Hand hygiene must be part of an integrated approach to infection control. Compliance with hand hygiene recommendations is poor worldwide. While the techniques involved in hand hygiene are simple, the complex interdependence of factors which determine hand hygiene behaviour makes the study of hand hygiene complex. It is now recognised that improving compliance with hand hygiene recommendations depends on altering human behaviour. Input from behavioural and social sciences is essential when designing studies to investigate compliance. Interventions to increase compliance with hand hygiene practices must be appropriate for different cultural and social needs. New strategies to promote hand hygiene worldwide include the formation of public-private partnerships.

Epidemiologic background of hand hygiene and evaluation of the most important agents for scrubs and rubs

The etiology of nosocomial infections, the frequency of contaminated hands with the different nosocomial pathogens, and the role of health care workers' hands during outbreaks suggest that a hand hygiene preparation should at least have activity against bacteria, yeasts, and coated viruses. The importance of efficacy in choosing the right hand hygiene product is reflected in the new Centers for Disease Control and Prevention guideline on hand hygiene (J. M. Boyce and D. Pittet, Morb. Mortal. Wkly. Rep. 51:1-45, 2002). The best antimicrobial efficacy can be achieved with ethanol (60 to 85%), isopropanol (60 to 80%), and n-propanol (60 to 80%). The activity is broad and immediate. Ethanol at high concentrations (e.g., 95%) is the most effective treatment against naked viruses, whereas n-propanol seems to be more effective against the resident bacterial flora. The combination of alcohols may have a synergistic effect. The antimicrobial efficacy of chlorhexidine (2 to 4%) and triclosan (1 to 2%) is both lower and slower. Additionally, both agents have a risk of bacterial resistance, which is higher for chlorhexidine than triclosan. Their activity is often supported by the mechanical removal of pathogens during hand washing. Taking the antimicrobial efficacy and the mechanical removal together, they are still less effective than the alcohols. Plain soap and water has the lowest efficacy of all. In the new Centers for Disease Control and Prevention guideline, promotion of alcohol-based hand rubs containing various emollients instead of irritating soaps and detergents is one strategy to reduce skin damage, dryness, and irritation. Irritant contact dermatitis is highest with preparations containing 4% chlorhexidine gluconate, less frequent with nonantimicrobial soaps and preparations containing lower concentrations of chlorhexidine gluconate, and lowest with well-formulated alcohol-based hand rubs containing emollients and other skin conditioners. Too few published data from comparative trials are available to reliably rank triclosan. Personnel should be reminded that it is neither necessary nor recommended to routinely wash hands after each application of an alcohol-based hand rub. Long-lasting improvement of compliance with hand hygiene protocols can be successful if an effective and accessible alcohol-based hand rub with a proven dermal tolerance and an excellent user acceptability is supplied, accompanied by education of health care workers and promotion of the use of the product.

Prevention and treatment of nosocomial sepsis in the NICU

Nosocomial sepsis is a serious problem for neonates who are admitted for intensive care. It is associated with an increase in mortality, morbidity, and prolonged length of hospital stay. Thus, both the human and fiscal costs of these infections are high. Although the rate of nosocomial sepsis increases with the degree of both prematurity and low birth weight, no specific lab test has been shown to be very useful in improving our ability to predict who has a "real" blood-stream infection and, therefore, who needs to be treated with a full course of antibiotics. As a result, antibiotic use is double the rate of "proven" sepsis and we are facilitating the growth of resistant organisms in the neonatal intensive care unit. The purpose of this article is to describe simple changes in process, which when implemented, can reduce nosocomial infection rates in neonates and improve outcomes.

A systematic review on the effectiveness of alcohol-based solutions for hand hygiene

The use of alcohol has been proposed as an option for hand hygiene. A systematic review was conducted to evaluate the clinical evidence supporting the use of alcohol-based solutions in hospitals as an option for hand hygiene. Studies published between January 1992 and April 2002 in English and Thai, related to the effectiveness of alcohol-based solutions, were reviewed. The databases searched included Medline, DARE, CINAHL and Dissertation Abstracts International. All studies were assessed as having adequate methodological quality. Results of this systematic review supported that alcohol-based hand rubbing removes microorganisms effectively, requires less time and irritates hands less often than does handwashing with soap or other antiseptic agents and water. Furthermore, the availability of bedside alcohol-based solutions increases compliance with hand hygiene among health care workers.

Effectiveness of Alcohol-based solutions for Hand Hygiene: A Systematic Review

: Hand hygiene is an important measure in reducing the transmission of nosocomial infections in hospitals, but adherence is poor among health care workers (HCWs).More rapid and effective hand disinfection procedures have been proposed, such as rubbing with alcohol.Hand rubbing with alcohol-based products is commonly used in some countries instead of handwashing. This review evaluates the scientific and clinical evidence on the use of alcohol-based hand rubs in health care settings as a new option for hand hygiene.

OBJECTIVES

To conduct a systematic review to determine the best available evidence related to effectiveness of alcohol-based solutions for hand hygiene. The specific review questions addressed were: the effectiveness in reducing microorganisms, compliance with hand hygiene, and the incidence of skin problems. Application time (consumption) addressed efficiency.

CRITERIA FOR CONSIDERING STUDIES IN THIS REVIEW

This review considered all studies that included alcohol-based solutions that related to the objectives of the review. Outcomes included measures for the reduction of organisms, compliance with hand hygiene, the types of skin problems, and application time. The review primarily considered any intra-individual trials (IITs), randomised controlled trials (RCTs) and controlled clinical trials (CCTs) relating to the effectiveness of alcohol-based solutions but also included quasi-experimental designs.

SEARCH STRATEGY FOR IDENTIFICATION OF STUDIES

The search sought to find published and unpublished studies. The databases searched included: Medline, CINAHL, ProQuest and Dissertation Abstracts International. Studies were additionally identified from reference lists of all studies retrieved.

ASSESSMENT AND DATA EXTRACTION

All studies were checked for methodological quality by two reviewers and data were extracted using a tool.

DATA ANALYSIS

The study results were pooled in statistical meta-analysis using Review Manager software and summarized in narrative form where statistical pooling was not appropriate or possible.

RESULTS

This systematic review included thirty seven studies that supports the use of alcohol-based solutions for routine hand hygiene and surgical hand scrub. Alcohol-based hand rub removes microorganisms from hands of personnel more effectively, requires less time, and irritates hands less often than traditional handwashing with nonmedicated soap or other antiseptic agents and water. The combination of 61% ethanol and 1% chlorhexidine gluconate (CHG) is even more effective in producing residual antibacterial properties on the skin. Furthermore, the availability of bedside alcohol-based solutions increased compliance with hand hygiene among HCWs.

CONCLUSION

Rubbing hands with alcohol-based agents has been proved to be effective in the reduction of microorganisms from hands. Alcohols are effective for preoperative cleaning of the hands of surgical personnel. Addition of CHG to alcohol-based solution can produce residual antibacterial properties on the skin. The use of alcohol-based solutions containing emollients causes less skin irritation and dryness and requires less time than washing hands with soap or other disinfectants. The promotion of bedside, alcohol-based hand rubs contributes to the increase in compliance with hand hygiene by HCWs.

Guideline for Hand Hygiene in Health-Care Settings. Recommendations of the Healthcare Infection Control Practices Advisory Committee and the HIPAC/SHEA/APIC/IDSA Hand Hygiene Task Force

The Guideline for Hand Hygiene in Health-Care Settings provides health-care workers (HCWs) with a review of data regarding handwashing and hand antisepsis in health-care settings. In addition, it provides specific recommendations to promote improved hand-hygiene practices and reduce transmission of pathogenic microorganisms to patients and personnel in health-care settings. This report reviews studies published since the 1985 CDC guideline (Garner JS, Favero MS. CDC guideline for handwashing and hospital environmental control, 1985. Infect Control 1986;7:231-43) and the 1995 APIC guideline (Larson EL, APIC Guidelines Committee. APIC guideline for handwashing and hand antisepsis in health care settings. Am J Infect Control 1995;23:251-69) were issued and provides an in-depth review of hand-hygiene practices of HCWs, levels of adherence of personnel to recommended handwashing practices, and factors adversely affecting adherence. New studies of the in vivo efficacy of alcohol-based hand rubs and the low incidence of dermatitis associated with their use are reviewed. Recent studies demonstrating the value of multidisciplinary hand-hygiene promotion programs and the potential role of alcohol-based hand rubs in improving hand-hygiene practices are summarized. Recommendations concerning related issues (e.g., the use of surgical hand antiseptics, hand lotions or creams, and wearing of artificial fingernails) are also included.

Guideline for Hand Hygiene in Health-Care Settings: recommendations of the Healthcare Infection Control Practices Advisory Committee and the HICPAC/SHEA/APIC/IDSA Hand Hygiene Task Force

The Guideline for Hand Hygiene in Health-Care Settings provides health-care workers (HCWs) with a review of data regarding handwashing and hand antisepsis in health-care settings. In addition, it provides specific recommendations to promote improved hand-hygiene practices and reduce transmission of pathogenic microorganisms to patients and personnel in health-care settings. This report reviews studies published since the 1985 CDC guideline (Garner JS, Favero MS. CDC guideline for handwashing and hospital environmental control, 1985. Infect Control 1986;7:231-43) and the 1995 APIC guideline (Larson EL, APIC Guidelines Committee. APIC guideline for handwashing and hand antisepsis in health care settings. Am J Infect Control 1995;23:251-69) were issued and provides an in-depth review of hand-hygiene practices of HCWs, levels of adherence of personnel to recommended handwashing practices, and factors adversely affecting adherence. New studies of the in vivo efficacy of alcohol-based hand rubs and the low incidence of dermatitis associated with their use are reviewed. Recent studies demonstrating the value of multidisciplinary hand-hygiene promotion programs and the potential role of alcohol-based hand rubs in improving hand-hygiene practices are summarized. Recommendations concerning related issues (e.g., the use of surgical hand antiseptics, hand lotions or creams, and wearing of artificial fingernails) are also included.

Comparison of different regimens for surgical hand preparation

Twenty surgical staff members participated in a clinical trial to compare the microbiology and skin condition of hands when using a traditional surgical scrub (TSS) with a detergent-based antiseptic containing 4% chlorhexidine gluconate (CHG) and a short application without scrub of a waterless hand preparation (HP) containing 61% ethyl alcohol, 1% CHG, and emollients. The HP was associated with less skin damage (P = .002) and lower microbial counts postscrub at days five (P = .002) and 19 (P = .02). The HP protocol had shorter contact time (HP mean [M] = 80.7 seconds; TSS M = 144.9 seconds; P < .0001), and more subjects preferred the HP regimen (P = .001). The HP performed better than the TSS, was less costly, and should be evaluated in larger trials and considered for widespread implementation.

A comparison of soap, alcohol and glove use during the nappy-changing procedure in a special care baby unit

This study was conducted in a special care baby unit (SCBU) in a district general hospital and concentrated on hand decontamination and glove-wearing during the nappy-changing procedure. The aims were to determine whether or not nurses were adhering to existing infection control policies and guidelines, and to determine the most appropriate product to be used for hand decontamination.

Nurses were observed carrying out nappy changes to determine their existing hand-washing and glove-wearing practices. A microbiological analysis of nurses' hands during the nappy change was performed in order to compare the effectiveness of soap, alcohol, and glove use in eliminating bacteria from the hands.

The observation study demonstrated that not all nurses were adhering to existing infection control policies and guidelines. The microbiological analysis found that on the majority of occasions, alcohol was better than soap at removing bacteria from the hands but that gloves provided the best protection overall for both babies and nurses by preventing the acquisition of bacteria.

Together these findings suggest that nurses' hands may be providing a route for the transmission of hospital-acquired infection in the SCBU. Ideally, nurses should be wearing gloves during the nappy-changing process and using alcohol to decontaminate their hands.

Relevance of carcass palpation in lambs to protecting public health

We recently reviewed the Food Safety and Inspection Service's (FSIS's) inspection procedures for lambs. As a result, FSIS published a Federal Register notice informing the public of its intent to change from an inspection system that requires extensive carcass palpation to an inspection system that requires no carcass palpation for lambs. This decision was based on the following three points. (i) Extensive carcass palpation in lambs does not routinely aid in the detection of food safety hazards that result in meat-borne illnesses. (ii) Hands are capable of spreading or adding contamination to the carcasses. (iii) FSIS inspection systems must reflect science-based decisions as they pertain to meat-borne illnesses consistent with a Pathogen Reduction/Hazard Analysis and Critical Control Point environment.

The permeability of dental procedure and examination gloves by an alcohol based disinfectant

OBJECTIVES

The usage of gloves in dentistry has increased greatly over the last 10 years and this has highlighted certain problems when gloves are being worn extensively. While skin irritations and allergies caused by latex proteins and accelerators have been the main focus of attention, dental materials such as disinfectants have also become known as a source of skin reactions. This study was performed to evaluate the permeability of various gloves by ethanol.

METHODS

The tip of the middle finger of 13 glove brands (natural latex gloves (NLG) powdered or unpowdered, powdered vinyl, nitrile and synthetic elastomer) was exposed to 5 ml of a hand disinfectant (Desderman). After a penetration time ranging from 2 min to 8 h the permeation of Desderman was detected with a gas chromatograph.

RESULTS

Only one component of the disinfectant (ethanol) could be detected to have gone through the gloves. After only 2 min the vinyl and one nitrile glove and after 10 min all glove types were permeated. Powder seemed to have no real influence on the penetration of ethanol. Some natural latex gloves showed a low rate of leakage, while vinyl and nitrile gloves were penetrated quickly and to a great extent. The synthetic elastomer (Biogel Neotech) was the only one with a significantly lower penetration even after 2-8 h.

SIGNIFICANCE

While there are reports of adverse skin reactions to alcohol the amount of ethanol (up to 40 microliters after 2 h) detected in this study is much too low to cause irritations and certainly not toxicity, but it could possibly initiate allergic reactions.

Handwashing facilities in the clinical area: a literature review

Handwashing is without doubt the most important intervention in the control of cross-infection. However, many healthcare staff do not comply with the procedure. One of the factors that contributes towards this is a lack of adequate and appropriate handwashing facilities. This article looks at the literature relating to handwashing and identifies what adequate and appropriate facilities actually are, with recommended standards for clinical areas. It concludes by highlighting that a greater commitment is needed from managers in this area in order to improve compliance with handwashing and therefore reduce infection rates.

Skin hygiene and infection prevention: more of the same or different approaches?

The purpose of this article is to review research indicating a link between hand hygiene and nosocomial infections and the effects of hand care practices on skin integrity and to make recommendations for potential changes in clinical practice and for further research regarding hand hygiene practices. Despite some methodological flaws and data gaps, evidence for a causal relationship between hand hygiene and reduced transmission of infections is convincing, but frequent handwashing causes skin damage, with resultant changes in microbial flora, increased skin shedding, and risk of transmission of microorganisms, suggesting that some traditional hand hygiene practices warrant reexamination. Some recommended changes in practice include use of waterless alcohol-based products rather than detergent-based antiseptics, modifications in lengthy surgical scrub protocols, and incorporation of moisturizers into skin care regimens of health care professionals.

Preliminary analysis of the transmission dynamics of nosocomial infections: stochastic and management effects

A simple mathematical model is developed for the spread of hand-borne nosocomial pathogens such as Staphylococcus aureus within a general medical-surgical ward. In contrast to previous models a stochastic approach is used. Computer simulations are used to explore the properties of the model, and the results are presented in terms of the pathogen's successful introduction rate, ward-level prevalence, and colonized patient-days, emphasizing the general effects of changes in management of patients and carers. Small changes in the transmissibility of the organism resulted in large changes in all three measures. Even small increases in the frequency of effective handwashes were enough to bring endemic organisms under control. Reducing the number of colonized patients admitted to the ward was also an effective control measure across a wide range of different situations. Increasing surveillance activities had little effect on the successful introduction rate but gave an almost linear reduction in colonized patient-days and ward-level prevalence. Shorter lengths of patient stay were accompanied by higher successful introduction rates, but had little effect on the other measures unless the mean time before detection of a colonized individual was large compared to the mean length of stay. We conclude that chance effects are likely to be amongst the most important factors in determining the course of an outbreak. Mathematical models can provide valuable insights into the non-linear interactions between a small number of processes, but for the very small populations found in hospital wards, a stochastic approach is essential.

Epidemiology and risk factors for nosocomial pneumonia. Emphasis on prevention

VAP is a complex nosocomial infection, the disease expression and resulting patient outcome of which is dependent on host factors, the causative organism, the timing and adequacy of treatment, and the presence of intrinsic or inducible antibiotic resistance. Significant improvements have been achieved in our ability to reduce the occurrence of VAP in the hospital setting. Clinicians caring for mechanically ventilated patients should strive to develop focused programs for the prevention of VAP, other nosocomial infections, and the occurrence of antibiotic-resistant infections at their institutions. The benefits of such programs are well demonstrated. The components of a PDSA (Plan-Do-STUDY-Act) model that can be simply employed to develop a VAP prevention program are as follows: Stages Plan: 1. Identify potentially modifiable risk factors for VAP at the institutional level. 2. Develop a strategy to modify or prevent the occurrence of these risk factors. [figure: see text] Do: 1. Carry out the planned intervention strategy. 2. Identify problems in the implementation of the designed intervention. 3. Update the intervention with solutions for the identified problems. 4. Collect basic data (e.g., VAP rates, severity of illness).

STUDY

1. Analyze data. 2. Summarize the results. Act: 1. Determine the overall success or failure of the intervention. 2. Identify potential modifications to improve the intervention strategy. 3. Prepare for next PDSA cycle. Inherent in the development and application of such programs is the concept that they are continuous processes striving to improve clinical performance over time (Fig. 3). At any given institution, the most likely approach to the prevention of NP and VAP will be a multifaceted one, employing interventions aimed at reducing the occurrence of aerodigestive tract colonization with pathogenic bacteria and aspiration. To be successful, such quality improvement programs must be embraced at the institutional level. Only in this way can hospitals hope to successfully reduce their rates of VAP and sustain or improve upon those efforts over time.

Effectiveness of hand-cleansing agents for removing Acinetobacter baumannii strain from contaminated hands

BACKGROUND

The effectiveness of hand-cleansing agents (plain liquid soap, 70% ethyl alcohol, 10% povidone-iodine, and 4% chlorhexidine gluconate) for removing a hospital strain of Acinetobacter baumannii from artificially contaminated hands of 5 volunteers was studied.

METHODS

The experiments were performed by using a Latin square statistical design, with two 5 x 4 randomized blocks, and the results were estimated by ANOVA. In the first and second blocks, the fingertips of the volunteers were contaminated with approximately 10(3) colony-forming units (light contamination hand) and 10(6) colony-forming units (heavy contamination hand), respectively.

RESULTS

In the first block, all products tested were effective, almost completely removing the microbial population of A baumannii artificially applied to the hands. In the second block, the use of hand-cleansing agents resulted in 91.36% (4% chlorhexidine), 92.33% (liquid soap), 98.49% (10% povidone-iodine), and 98.93% (70% ethyl alcohol) reduction in counts of A baumannii cells applied to the fingertips. The ethyl alcohol and povidone-iodine had significantly higher removal rates than plain soap and chlorhexidine (P <.05).

CONCLUSIONS

These results suggest that 70% ethyl alcohol and 10% povidone-iodine may be the most effective hand-cleansing agents for removing A baumannii strain from heavily contaminated hands (10(6) colony-forming units/fingertip).

The effect of new disinfectant substances on the metabolism of Enterobacter cloacae

The antimicrobial mechanism of 16 new commercially manufactured disinfectant substances on an Enterobacter cloacae strain was studied. The substances tested represent 11 quaternary ammonium salts (QAS) and five combinated QAS with other ingredients. The antimicrobial efficacy was characterized by influencing the growth of bacterial cells expressed by MIC and ED50 values as well as by the inhibition of the incorporation rate of [14C] adenine and [14C] leucine. The disinfectants are divided into three groups according to their efficacy. The first group comprised substances with strong inhibitory effect (MIC 0.006-0.048 mg l(-1)) such as triquart, topax 91, benzalkonium chloride, neoquat S, ID 213, and antibacteric P. The second group represented substances with good antibacterial efficacy (MIC 0.048-0.15 mg l(-1)), and the third group were substances with MIC values up to 0.195-0.39 mg l(-1). Cetrimide had low activity (MIC 3.12-6.25 mg l(-1)). The effect of substances studied on the biosynthetic processes expressed by R values (IC50 Ade:IC50 Leu) showed that these values were < 1 except ADL 007. Much lower IC50 Ade and IC50 Leu values of the disinfectant substances studied suggested interference of these substances with nucleic acid synthesis and proteins synthesis which was expressed by inhibition of both precursors. All substances except cetrimide caused an inhibition of the endogenous respiration. The highest inhibition was caused by benzalkonium chloride. This affected the respiration significantly in the presence of intermediators of the Krebs' cycle (glycerol, aspartate). The tested substance suppressed the growth of E. cloacae probably through interference with energy-yielding and energy-requiring processes of the cells.

A 4-year longitudinal study of the oral prevalence of enteric gram-negative rods and yeasts in Chinese children

A 4-year longitudinal study of the oral prevalence of enteric gram-negative rods and yeasts in 116 Chinese primary school children in Hong Kong was conducted. The oral prevalence of enteric gram-negative rods for each consecutive year was 25.3%, 37.0%, 24.0% and 25.8% respectively, with a weighted mean of 27.9%. Enterobacteriaceae, which comprised 57% of all enteric gram-negative rods, were more common in children with no caries experience. The oral prevalence of yeasts for each consecutive year was 7.7%, 12.0%, 14.4% and 15.5% respectively, with a weighted mean of 12.5%. Candida albicans comprised 84% of all yeasts isolated. Oral yeast carriage was significantly associated with caries prevalence. While the oral prevalence of enteric gram-negative rods in primary school children in Hong Kong may be higher than in other parts of the world, repeated isolation of either enteric gram-negative rods or Candida spp. from individual children over the 4-year study period was rare, suggesting that carriage of these organisms is transient.

Enterobacter spp.: pathogens poised to flourish at the turn of the century

Knowledge of the genus Enterobacter and its role in human disease has expanded exponentially in recent years. The incidence of infection in the hospital and the community has increased. New clinical syndromes have been recognized. Enterobacter spp. have also been implicated as causes of other syndromes that traditionally have been associated almost exclusively with more easily treatable pathogens, such as group A streptococci and staphylococci. Rapid emergence of multiple-drug resistance has been documented in individual patients during therapy and in populations and environments with strong selective pressure from antimicrobial agents, especially the cephalosporins. Therapeutic options for patients infected with multiply resistant strains have become severely limited. Carbapenems or, alternatively, fluoroquinolones are the most predictively active options, although resistance to both classes has been observed on rare occasions. Enterobacter spp. appear well adapted for survival and even proliferation as the turn of the century approaches.

Nurses' infection-control practice: hand decontamination, the use of gloves and sharp instruments

Infection is an acknowledged hospital problem. Micro-organisms are disseminated mainly via hands but there is evidence that hand decontamination, the most important means of prevention, is performed too seldom, and not always after activities likely to result in heavy contamination. Nurses themselves are exposed to risks of infection, chiefly through contact with blood and body fluids, yet it has also been reported that gloves are not always worn during contact with patients' secretions and that the handling and disposal of sharp instruments may be performed unsafely. The study reported in this paper documents nursing behaviour in relation to hand decontamination, the use of gloves and sharps, taking into consideration a number of variables which could influence practice: availability of the expertise afforded by an infection-control nurse, clinical setting, nursing workload, knowledge and the resources available to control infection. Hands were decontaminated after 28.78% of patient contacts. Hands were decontaminated after 49.85% of activities likely to result in heavy contamination. Performance was related to nursing workload and the availability of hand decontaminating agents, especially when the nurses became busy. Use of gloves when they were available also proved good, with little evidence of wasteful use. The handling and disposal of sharps were commendable for most subjects but a few grossly unsafe incidents were nevertheless witnessed, apparently not associated with any of the variables examined.

The effects of 'in-use' surgical handwashing on the pre- and postoperative fingertip flora during cardiothoracic and orthopaedic surgery

Two operating teams (25 persons) were followed for two months with fingerprint samples taken preoperatively; before and after 'in-use' surgical handwashing; and immediately postoperatively, with and without surgical gloves. The mean time for handwashing for the cardiothoracic team (CT) was 2 min and for the orthopaedic team (OT) was 3.5 min. A closer observation of 10 persons revealed a great individual variation in washing techniques, in spite of standard guidelines. The CT team performed eight, and the OT team nine sterile operations with an average duration of 3 h and 20 min and 2 h and 40 min, respectively. Surgical handwashing resulted in fingertip sterility in 111/118 (94.1%) cases; in 61/66 (92.4%) samples from the surgeons and in 50/52 (96.2%) samples from the assistants. Postoperative fingerprinting with gloves on showed sterile conditions in 85/91 (93.4%) samples; 57/59 (96.6%) from the surgeons and 28/32 (87.5%) from the assistants. Immediately after removal of the gloves, 43/67 (64.2%) of fingerprint samples from the surgeons and 13/48 (27.1%) from the assistants were still sterile. Coagulase-negative staphylococci (CNS) and Bacillus species predominated in fingerprint samples. Of the 105 CNS strains tested, 11.4% were methicillin resistant. Only five strains of Staphylococcus aureus were isolated; in 4/5 cases from the OT. This study illustrates that in spite of standard guidelines, there is great individual variation in surgical handwashing. However, in most instances, the bacteria are eradicated from the fingertips. Even after surgery for 2-3 h, there may still be a residual effect of the hand disinfecting agent in half of the cases.

Gram-negative bacteria. The challenge of preventing cross-infection in hospital wards: a review of the literature

Gram-negative bacteria are responsible for a high proportion of nosocomial infections, particularly among the critically ill and those in hospital for long periods. Colonization (asymptomatic carriage on the skin) occurs before the emergence of overt clinical infection (appearance of the signs and symptoms of disease) and is therefore worth reducing. Spread is principally via the hands of staff, so handwashing is the chief method of prevention. Gram-negative bacteria survive best in a moist environment and are more readily transferred via damp than dry surfaces; hands and equipment should therefore be kept as dry as possible. Good skin can also help prevent cross-infection as Gram-negative bacteria colonize damaged skin more readily than if it is in good condition.

Enterobacter cloacae cross-colonization in neonates demonstrated by ribotyping

The intestinal colonization by Enterobacter cloacae strains with a derepressed cephalosporinase was studied in a paediatric ward between February 1990 and January 1991. Environmental sampling was performed simultaneously. Fifty-two isolates were recovered from 200 neonates (stool, blood) and 14 strains were isolated from the neonatal environment. An epidemiological study based on the typing of 36 Enterobacter cloacae isolates was carried out using antibiotyping, biotyping and ribotyping methods. The isolates selected were from 21 neonates (24 isolates), the neonatal ward environment (8 isolates) and from other wards (4 isolates). Thirty-two isolates had the same antibiotic resistance pattern, corresponding to a derepressed cephalosporinase and resistance to the following aminoglycosides: kanamycin, gentamicin, tobramycin and netilmicin. No predominant biotyping pattern could be established. Ribotyping done with two endonucleases (EcoRI and BamHI) showed 28 Enterobacter cloacae isolates to have a single pattern. Ribotyping was the most discriminating method used in this study, permitting identification of cross-contamination with Enterobacter cloacae in the paediatric ward.