Skin irritation and dryness associated with two hand-hygiene regimens: soap-and-water hand washing versus hand antisepsis with an alcoholic hand gel

Short-term effects of alcohol-based disinfectant and detergent on skin irritation

The most important risk factor for occupational contact dermatitis in hospital personnel is the exposure to irritants such as water, detergents and alcohol-based solutions. This study was undertaken to evaluate the short-term effects of repeated exposure to an alcohol-based disinfectant, to a detergent and to an alcohol-based disinfectant/detergent alternately. The hardening effect in preirritated skin after a 4-week interval was also evaluated. Detergent, disinfectant and disinfectant/detergent alternately were applied daily every 15 min for 6 h for 2 days to the flexor upper arms and forearms of 15 volunteers. A control area was included. After 4 weeks, a sodium lauryl sulfate patch was applied to each area. Irritant reactions were quantified by visual score, transepidermal water loss (TEWL) and skin colour at baseline, D3, D8, D35 and D37. As evaluated by clinical assessment, detergent caused more redness of the skin than both disinfectant applied alone and disinfectant/detergent alternately at D3 and D8, P < 0.001 and P < 0.001, respectively. An increased irritant response for detergent as compared to disinfectant alone and disinfectant/detergent was confirmed by TEWL and colour evaluations, P = 0.001 and P = 0.001 and P = 0.006 and P = 0.009, respectively. No hardening effect in preirritated skin was found after a 4-week interval. In conclusion, hand disinfection with alcohol-based disinfectant or alternate use of disinfectant/detergent causes less skin irritation than hand disinfection with a detergent. This study evaluated the short-term effects of disinfectant and detergent exposure only, and more long-term studies are necessary before recommendations can be made.

Decreasing hospital-associated rotavirus infection: a multidisciplinary hand hygiene campaign in a children's hospital

OBJECTIVE

Hand hygiene is an effective means of preventing hospital-associated infection, but compliance among health care workers is poor. Few studies aimed at increasing hand hygiene in the hospital setting have shown sustained improvement and concurrent decreases in hospital-associated infections, and even fewer have been performed in the pediatric setting.

METHODS

We implemented a hand hygiene program with the hopes of improving hand hygiene and decreasing hospital-associated rotavirus infection rates. A multidisciplinary group developed a hospital supported, house-wide campaign. Opportunities for hand hygiene were observed during 5 periods. The frequency of hospital-associated rotavirus infection was tracked over time by review of laboratory records. Correlates of hand hygiene were investigated with the use of multivariate logistic regression.

RESULTS

Overall hand hygiene compliance improved from 62% in period 1 to 81% in period 5 (P < 0.001). Soap and water was the most common method for practicing hand hygiene, and alcohol hand gel use increased from 4% to 29% between the first and last observation periods (P < 0.001). The rate of hospital-associated rotavirus infection decreased from 5.9 episodes per 1000 discharged patients in 2001 to 2.2 episodes per 1000 discharged patients in 2004 (P = 0.01). Period of observation, hospital ward, type of care provider and type of care performed were all independently associated with hand hygiene (adjusted P < or = 0.02 for all).

CONCLUSION

Improving hand hygiene is an important goal for health care institutions. These data can be useful for development of interventions aimed at improving hand hygiene.

An alcohol hand rub containing a synergistic combination of an emollient and preservatives: prolonged activity against transient pathogens

A new alcohol-based hand antiseptic (Octoxy hand rub) containing a synergistic combination of an emollient (Octoxyglycerine) and preservatives was developed and evaluated for immediate and prolonged activity against transient bacteria. The in vitro and in vivo antimicrobial efficacy was compared with other alcohol hand rubs containing preservative/antimicrobial (Prevacare and Avagard). In vitro evaluation was carried out using a tube-dilution method and a pig-skin model. Rapid and prolonged efficacy in vivo was evaluated against Staphylococcus epidermidis on the hands of volunteers. Octoxy hand rub was 100% effective in rapidly killing pathogens including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium in vitro. In volunteers, all three hand rubs gave a significant reduction in microbial count within 15s. Octoxy hand rub showed significantly higher efficacy against S. aureus and Escherichia coli than Avagard and Prevacare 15 min after application to the pig-skin model, and against S. epidermidis in both the pig-skin model and in volunteers. Use of Octoxy hand rub with broad-spectrum immediate and prolonged antimicrobial activity may be a very effective way of improving hand hygiene without exposing the hands to higher concentrations of antimicrobials.

Illness transmission in the home: a possible role for alcohol-based hand gels

OBJECTIVES

The widespread use of child care has altered the epidemiology of respiratory and gastrointestinal (GI) infection in the community. Our primary objective was to measure transmission of respiratory and GI illnesses among families with children enrolled in child care. We also sought to examine potential predictors of reduced illness transmission in the home in a secondary analysis.

METHODS

We performed an observational, prospective cohort study to determine transmission rates for respiratory and GI illnesses within families with at least 1 child between 6 months and 5 years of age enrolled in child care. A survey about family beliefs and practices was mailed at the beginning of the study. Symptom diaries were provided for families to record the timing and duration of respiratory and GI illnesses. To ensure the accuracy of symptom diaries, biweekly telephone calls were performed to review illnesses recorded by participants. Families with > or =4 weeks of data recorded were included in the analysis. Families were recruited from 5 pediatric practices in the metropolitan Boston area. Of 261 families who agreed to participate in the study, 208 were available for analysis. Secondary transmission rates for respiratory and GI illnesses were measured as illnesses per susceptible person-month.

RESULTS

We observed 1545 respiratory and 360 GI illnesses in 208 families from November 2000 to May 2001. Of these, 1099 (71%) respiratory and 297 (83%) GI illnesses were considered primary illnesses introduced into the home. The secondary transmission rates for respiratory and GI illnesses were 0.63 and 0.35 illnesses per susceptible person-month, respectively. Only two thirds of respondents correctly believed that contact transmission was important in the spread of colds, and fewer than half believed that it was important in the spread of stomach flus. Twenty-two percent of respondents reported use of alcohol-based hand gels all, most, or some of the time; 33% reported always washing their hands after blowing or wiping a nose. In multivariate models, use of alcohol-based hand gels had a protective effect against respiratory illness transmission in the home.

CONCLUSIONS

In homes with young children enrolled in child care, illness transmission to family members occurs frequently. Alcohol-based hand gel use was associated with reduced respiratory illness transmission in the home.

Infection control policies and hospital-associated infections among surgical patients: variability and associations in a multicenter pediatric setting

BACKGROUND

Hospital-associated infections are an important cause of patient morbidity and death. Little is known about the variability of infection rates and infection control practices among pediatric hospitals.

METHODS

This cross-sectional study was performed with the Pediatric Health Information System database, which includes demographic and diagnostic data for 35 freestanding, noncompeting, children's hospitals, and with data from a survey of the hospitals, which yielded additional information on infection control policies and practices. Patients undergoing elective surgical procedures were included in this study.

RESULTS

Of the 35 eligible hospitals, 31 (89%) chose to participate in the survey component of this study. A total of 48278 patients met the inclusion criteria for the study; 2.3% of these patients had respiratory infections and 0.8% had gastrointestinal infections. The frequency of patients diagnosed with respiratory or gastrointestinal infections varied considerably among the hospitals and ranged from <1% to 6%. Certain infection control processes also varied among the hospitals during the study period. For instance, of the 31 hospitals, 12 monitored hand hygiene, 19 had administrative support of hand hygiene, and 16 had alcohol hand gel present for the entire study period. The presence of alcohol hand gel for the entire study was strongly and independently associated with lower odds of gastrointestinal infections (adjusted odds ratio: 0.64; 95% confidence interval: 0.49-0.85).

CONCLUSIONS

Hospitals should support the use of alcohol hand gel, with the aim of decreasing hospital-associated infection rates.

Assessment of the antibacterial activity of tea tree oil using the European EN 1276 and EN 12054 standard suspension tests

The activity of tea tree oil (TTO) and TTO-containing products was investigated according to the EN 1276 and EN 12054 European suspension methods. The activity of different concentrations of TTO, a hygienic skin wash (HSW), an alcoholic hygienic skin wash (AHSW) and an alcoholic hand rub (AHR) was investigated. These formulations were assessed in perfect conditions with the EN 12054 test, and in perfect conditions as well as in the presence of interfering substances with the EN 1276 test, against Staphylococcus aureus, Acinetobacter baumannii, Escherichia coli and Pseudomonas aeruginosa. With the latter test, the activity of the same formulations without TTO was also assessed as a control. With the EN 1276 test, the AHR achieved a >10(5)-fold reduction against all four test organisms within a 1-min contact time. The AHSW achieved a >or=10(5)-fold reduction against A. baumannii after a 1-min contact time and against S. aureus, E. coli and P. aeruginosa after a 5-min contact time. The efficacy of TTO appeared to be dependent on the formulation and the concentration tested, the concentration of interfering substances and, lastly, the organism tested. Nevertheless, 5% TTO achieved a >10(4)-fold reduction in P. aeruginosa cell numbers after a 5-min contact time in perfect conditions. TTO (5%) in 0.001% Tween 80 was significantly more active against E. coli and P. aeruginosa than against S. aureus and A. baumannii. With the EN 12054 test, after a 1-min contact time, 5% TTO in 0.001% Tween 80 and the AHSW achieved a >10(4)-fold reduction in E. coli and A. baumannii cell numbers, respectively, and the AHR achieved a >4 log10 reduction against all organisms tested. The formulations used in this study are now being tested using a novel ex vivo method as well as the in vivo European standard handwashing method EN 1499.

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.

Skin protection in nursing work: promoting the use of gloves and hand alcohol

Nursing has been identified as a wet-work occupation, with a high prevalence of occupational irritant contact dermatitis. Reduction of exposure to skin irritants contributes to the prevention of occupational skin disease in nurses. The role of the use of soap and water, hand alcohol and gloves in prevention programmes is discussed. 2 additional measures for reducing exposure to skin irritants are postulated: use of hand alcohol instead of soap and water in disinfection procedures when the hands are not visibly dirty; use of gloves in wet activities such as patient washing to prevent the hands from becoming wet and visibly dirty. We investigated the effectiveness of these recommendations in a model. Mean daily wet-work exposure during nursing work was modelled: regular model. We also modelled exposure to skin irritants in combination with the implementation of these recommendations: prevention model. The hands of healthy volunteers were exposed to the regular or the prevention model over 3 weeks for 5 days a week. The change in transepidermal water loss (TEWL) on the back of the hands was measured after 3 weeks of exposure to these wet-work simulations. An increase in TEWL occurred with the regular model, while mean TEWL decreased in the prevention model. Skin irritation from occlusion by gloves appeared to be more pronounced in the regular model compared to the prevention model. The results of this study justify the conclusion that in nursing work, hand alcohol is the preferred disinfectant. Although the prevention model implies increased occlusive exposure, this has no additional irritant effect, probably because of the absence of soap exposure.

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.

Hand hygiene: improved standards and practice for hospital care

PURPOSE OF REVIEW

To review the most recently published literature on hand hygiene practices in healthcare settings.

RECENT FINDINGS

Adherence with recommendations for hand hygiene remains low, but key factors of noncompliance have been identified and corrective actions proposed. Current guidelines recommend the use of alcohol-based handrub formulations as the new standard of care, thus requiring a system change in most hospitals. In addition, healthcare worker education and motivation are obviously important to modify hand hygiene behavior and must be part of multimodal strategies to enhance compliance in hospitals. Compliance improvement is associated with reduced infection rates and resistance spread. Handrub application according to recommended practices is an alternative to conventional surgical handscrubbing with antiseptic soap and water for surgical hand preparation.

SUMMARY

System change must be addressed in most hospitals where alcohol-based handrubbing has not become a standard of care. Strategies to improve hand hygiene compliance must be multimodal and include staff education and motivation, the use of performance indicators, and hospital management support. Successful campaigns will result in reduced infection rates, antimicrobial resistance spread, and enhance patient safety.

SHEA guideline for preventing nosocomial transmission of multidrug-resistant strains of Staphylococcus aureus and enterococcus

BACKGROUND

Infection control programs were created three decades ago to control antibiotic-resistant healthcare-associated infections, but there has been little evidence of control in most facilities. After long, steady increases of MRSA and VRE infections in NNIS System hospitals, the Society for Healthcare Epidemiology of America (SHEA) Board of Directors made reducing antibiotic-resistant infections a strategic SHEA goal in January 2000. After 2 more years without improvement, a SHEA task force was appointed to draft this evidence-based guideline on preventing nosocomial transmission of such pathogens, focusing on the two considered most out of control: MRSA and VRE.

METHODS

Medline searches were conducted spanning 1966 to 2002. Pertinent abstracts of unpublished studies providing sufficient data were included.

RESULTS

Frequent antibiotic therapy in healthcare settings provides a selective advantage for resistant flora, but patients with MRSA or VRE usually acquire it via spread. The CDC has long-recommended contact precautions for patients colonized or infected with such pathogens. Most facilities have required this as policy, but have not actively identified colonized patients with surveillance cultures, leaving most colonized patients undetected and unisolated. Many studies have shown control of endemic and/or epidemic MRSA and VRE infections using surveillance cultures and contact precautions, demonstrating consistency of evidence, high strength of association, reversibility, a dose gradient, and specificity for control with this approach. Adjunctive control measures are also discussed.

CONCLUSION

Active surveillance cultures are essential to identify the reservoir for spread of MRSA and VRE infections and make control possible using the CDC's long-recommended contact precautions.

[Morbidity and mortality of very-low-birth-weight infants as an indicator of the quality of perinatal care]

OBJECTIVE

To compare the clinical outcomes of a cohort of very low birth weight (VLBW) infants who received healthcare in our unit from 1994-2000 with all the variables included in the Vermont-Oxford Network (VON) database.

METHODS

A historical cohort of 417 VLBW live infants born in our center from 1994-2000 was evaluated. The 80 variables of the VON already prospectively included in the unit's database were used and a further 20 variables were added through retrospective review of medical records. The rates of perinatal risk factors, interventions, and causes of morbidity were analyzed and the periods 1994-1997 and 1998-2000 were compared. We also compared these rates with those reported by the VON.

RESULTS

Comparison of the results in both periods showed an increase in the percentage of multiple pregnancies and prenatal corticosteroid exposure, as well as in the early use of surfactant and continuous positive pressure. The incidence of intraventricular hemorrhage decreased, but no differences were observed in other outcomes. Our rates of Cesarean sections and multiple births, as well as the use of prenatal steroids, were higher than those of the VON. The outcomes of infants receiving healthcare in our unit were similar to those of the VON but mortality in infants weighing < 800 g was slightly higher, coinciding with higher rates of late sepsis.

CONCLUSION

Morbidity rates in VLWB infants receiving care in our unit decreased during the period studied and compared favorably with those reported by the VON. Alltogether, our results indicate that the quality of care in our perinatal center is good. General use of this methodology would permit comparison of outcomes and quality of care across regions and nations, as well as across Europe, in a recently established network (EuroNeoNet.com).

Use of alcohol hand sanitizer as an infection control strategy in an acute care facility

BACKGROUND

Nosocomial infections are a major problem in health care facilities, resulting in extended durations of care, substantial morbidity and mortality, and excess costs. Since alcohol gel hand sanitizers combine high immediate antimicrobial efficacy with ease of use, this study was carried out to determine the effect of the use of an alcohol gel hand sanitizer by caregivers on infection types and rates in an acute care facility. Patients were educated about the study through a poster on the unit, and teachable patients were given portable bottles of the alcohol hand gel for bedside use, along with an educational brochure explaining how and why to practice good hand hygiene.

METHODS

Infection rate and type data were collected in 1 unit of a 498-bed acute care facility for 16 months (February 2000 to May 2001). An alcohol gel hand sanitizer was provided and used by caregivers in the orthopedic surgical unit of the facility during this period.

RESULTS

The primary infection types (more than 80%) found were urinary tract (UTI) and surgical site (SSI) infections. Infection types and rates for the unit during the period the alcohol hand sanitizer (intervention) was used were compared with the infection types and rates for the same unit when the alcohol hand sanitizer was not used (baseline); the results demonstrated a 36.1% decrease in infection rates for the 10-month period that the hand sanitizer was used.

CONCLUSION

This study indicates that use of an alcohol gel hand sanitizer can decrease infection rates and provide an additional tool for an effective infection control program in acute care facilities.

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.

Use of an alcohol-based hand rub and quality improvement interventions to improve hand hygiene in a Russian neonatal intensive care unit

BACKGROUND

Hand hygiene (HH) is critical to infection control, but compliance is low. Alcohol-based antiseptics may improve HH. HH practices in Russia are not well described, and facilities are often inadequate.

SETTING

Four 6-bed units in a neonatal intensive care unit in St. Petersburg, Russia.

METHODS

Prospective surveillance of HH compliance, nosocomial colonization, and antibiotic administration was performed from January until June 2000. In February 2000, alcohol-based hand rub was provided for routine HH use. Eight weeks later, a quality improvement intervention was implemented, consisting of review of interim data, identification of opinion leaders, posting of colonization incidence rates, and regular feedback. Means of compliance, colonization, and antibiotic use were compared for periods before and after each intervention.

RESULTS

A total of 1,027 events requiring HH were observed. Compliance was 44.2% before the first intervention, 42.3% between interventions, and 48% after the second intervention. Use of alcohol rose from 15.2% of HH indications to 25.2% between interventions and 41.5% after the second intervention. The incidence of nosocomial colonization (per 1,000 patient-days) with Klebsiella pneumoniae was initially 21.5, decreased to 4.7, and then was 3.2 in the final period. Rates of antibiotic and device use also decreased.

CONCLUSIONS

HH may have increased slightly, but the largest effect was a switch from soap and water to alcohol which may have been associated with decreased cross-transmission of Klebsiella, although this may have been confounded by lower device use. Alcohol-based antiseptic may be an improvement over current practices, but further research is required.

Adverse reactions associated with an alcohol-based hand antiseptic among nurses in a neonatal intensive care unit

BACKGROUND

Alcohol-based hand antiseptics are strongly recommended in the 2002 Centers for Disease Control and Prevention's hand-hygiene guideline. In a study comparing 2 hand-hygiene regimes, an alcohol-based (61% ethyl) antiseptic and a detergent containing 2% chlorhexidine gluconate in 2 neonatal intensive care units, we noted adverse reactions associated with the alcohol-based antiseptic.

METHODS

A prospective study was conducted of the skin condition of 58 nurses using an alcohol-based product from March 2001 to January 2002. Adverse reactions to the alcohol-based product were noted and the Fisher exact test was used to determine factors associated with these reactions. Nurses with reactions to the alcohol product who were available to follow-up were patch tested to the product.

RESULTS

Of 58 (1.1/100 nursing mo) nurses, 7 were evaluated by occupational health services for dermatologic symptoms that varied from mild to severe after use of the alcohol product, but 4 of 7 have resumed use. Nurses who had adverse reactions develop had been employed on the study unit and in the nursing profession for significantly less time than those with no reactions (P =.037 and P =.002, respectively), and were significantly more likely to report a history of itchy, sore skin (P =.047). A positive patch-test result was noted in 3 of 4 nurses with a previous reaction to the product.

CONCLUSION

This case series will alert users in the United States and elsewhere to the nature of reactions to alcohol products and how these reactions differ from reactions to traditional hand antiseptic products.

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.

Guidelines for the prevention of intravascular catheter-related infections

BACKGROUND

Although many catheter-related bloodstream infections (CRBSIs) are preventable, measures to reduce these infections are not uniformly implemented.

OBJECTIVE

To update an existing evidenced-based guideline that promotes strategies to prevent CRBSIs.

DATA SOURCES

The MEDLINE database, conference proceedings, and bibliographies of review articles and book chapters were searched for relevant articles.

STUDIES INCLUDED

Laboratory-based studies, controlled clinical trials, prospective interventional trials, and epidemiologic investigations.

OUTCOME MEASURES

Reduction in CRBSI, catheter colonization, or catheter-related infection.

SYNTHESIS

The recommended preventive strategies with the strongest supportive evidence are education and training of healthcare providers who insert and maintain catheters; maximal sterile barrier precautions during central venous catheter insertion; use of a 2% chlorhexidine preparation for skin antisepsis; no routine replacement of central venous catheters for prevention of infection; and use of antiseptic/antibiotic-impregnated short-term central venous catheters if the rate of infection is high despite adherence to other strategies (ie, education and training, maximal sterile barrier precautions, and 2% chlorhexidine for skin antisepsis).

CONCLUSION

Successful implementation of these evidence-based interventions can reduce the risk for serious catheter-related infection.

Guidelines for the Prevention of Intravascular Catheter–Related Infections

These guidelines have been developed for practitioners who insert catheters and for persons responsible for surveillance and control of infections in hospital, outpatient, and home health-care settings. This report was prepared by a working group comprising members from professional organizations representing the disciplines of critical care medicine, infectious diseases, health-care infection control, surgery, anesthesiology, interventional radiology, pulmonary medicine, pediatric medicine, and nursing. The working group was led by the Society of Critical Care Medicine (SCCM), in collaboration with the Infectious Disease Society of America (IDSA), Society for Healthcare Epidemiology of America (SHEA), Surgical Infection Society (SIS), American College of Chest Physicians (ACCP), American Thoracic Society (ATS), American Society of Critical Care Anesthesiologists (ASCCA), Association for Professionals in Infection Control and Epidemiology (APIC), Infusion Nurses Society (INS), Oncology Nursing Society (ONS), Society of Cardiovascular and Interventional Radiology (SCVIR), American Academy of Pediatrics (AAP), and the Healthcare Infection Control Practices Advisory Committee (HICPAC) of the Centers for Disease Control and Prevention (CDC) and is intended to replace the Guideline for Prevention of Intravascular Device–Related Infections published in 1996. These guidelines are intended to provide evidence-based recommendations for preventing catheter-related infections. Major areas of emphasis include 1) educating and training health-care providers who insert and maintain catheters; 2) using maximal sterile barrier precautions during central venous catheter insertion; 3) using a 2% chlorhexidine preparation for skin antisepsis; 4) avoiding routine replacement of central venous catheters as a strategy to prevent infection; and 5) using antiseptic/antibiotic impregnated short-term central venous catheters if the rate of infection is high despite adherence to other strategies (i.e., education and training, maximal sterile barrier precautions, and 2% chlorhexidine for skin antisepsis). These guidelines also identify performance indicators that can be used locally by health-care institutions or organizations to monitor their success in implementing these evidence-based recommendations.

Guidelines for the prevention of intravascular catheter-related infections

BACKGROUND

Although many catheter-related bloodstream infections (CR-BSIs) are preventable, measures to reduce these infections are not uniformly implemented.

OBJECTIVE

To update an existing evidenced-based guideline that promotes strategies to prevent CR-BSIs.

DATA SOURCES

The MEDLINE database, conference proceedings, and bibliographies of review articles and book chapters were searched for relevant articles.Studies Included: Laboratory-based studies, controlled clinical trials, prospective interventional trials, and epidemiological investigations.

OUTCOME MEASURES

Reduction in CR-BSI, catheter colonization, or catheter-related infection.

SYNTHESIS

The recommended preventive strategies with the strongest supportive evidence are education and training of healthcare providers who insert and maintain catheters; maximal sterile barrier precautions during central venous catheter insertion; use of a 2% chlorhexidine preparation for skin antisepsis; no routine replacement of central venous catheters for prevention of infection; and use of antiseptic/antibiotic impregnated short-term central venous catheters if the rate of infection is high despite adherence to other strategies (i.e. education and training, maximal sterile barrier precautions and 2% chlorhexidine for skin antisepsis).

CONCLUSION

Successful implementation of these evidence-based interventions can reduce the risk for serious catheter-related infection.

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.

Dermal tolerance and effect on skin hydration of a new ethanol-based hand gel

We studied the dermal tolerance (repetitive occlusive patch test; ROPT) and the skin hydrating properties of a new ethanol-based gel [85% (w/w)], Sterillium Gel. For the ROPT, 53 participants were studied. Gel was applied to one site on the back under an occlusive patch during an induction phase (nine applications over three weeks) and two weeks later to a virgin site on the back during a challenge phase (one application). Twenty-four hours after the removal of the patches (induction phase and challenge phase), then 48 and 72 h later (challenge phase) sites were graded for skin reactions using a standardized scale. In the induction phase none of the 53 participants had a skin reaction. In the challenge phase one participant had a barely perceptible skin reaction, and one had mild erythema at one time point. To evaluate skin hydrating properties of the gel, treated skin of 21 participants was compared to untreated skin. The gel was applied twice a day to the forearm for 14 days. Control corneometer values were taken before application of the gel (mean: 32.7 +/- 5.0) and after one (36.3 +/- 4.4) and two weeks (36.1 +/- 5.4). Relative skin hydration on treated skin in comparison with an untreated control field was significantly higher after one week by 6.85% (P = 0.0031; paired t -test for dependent samples) and after two weeks by 4.47% (P = 0.0153). Sterillium Gel did not demonstrate a clinically relevant potential for dermal irritation or sensitization, and significantly increased skin hydration after repetitive use, and so could enhance compliance with hand hygiene among healthcare workers.

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.

Guidelines for the prevention of intravascular catheter-related infections. The Hospital Infection Control Practices Advisory Committee, Center for Disease Control and Prevention, U.S

These guidelines have been developed for practitioners who insert catheters and for persons responsible for surveillance and control of infections in hospital, outpatient, and home health-care settings. This report was prepared by a working group comprising members from professional organizations representing the disciplines of critical care medicine, infectious diseases, health-care infection control, surgery, anesthesiology, interventional radiology, pulmonary medicine, pediatric medicine, and nursing. The working group was led by the Society of Critical Care Medicine (SCCM), in collaboration with the Infectious Disease Society of America (IDSA), Society for Healthcare Epidemiology of America (SHEA), Surgical Infection Society (SIS), American College of Chest Physicians (ACCP), American Thoracic Society (ATS), American Society of Critical Care Anesthesiologists (ASCCA), Association for Professionals in Infection Control and Epidemiology (APIC), Infusion Nurses Society (INS), Oncology Nursing Society (ONS), Society of Cardiovascular and Interventional Radiology (SCVIR), American Academy of Pediatrics (AAP), and the Healthcare Infection Control Practices Advisory Committee (HICPAC) of the Centers for Disease Control and Prevention (CDC) and is intended to replace the Guideline for Prevention of Intravascular Device-Related Infections published in 1996. These guidelines are intended to provide evidence-based recommendations for preventing catheter-related infections. Major areas of emphasis include 1) educating and training health-care providers who insert and maintain catheters; 2) using maximal sterile barrier precautions during central venous catheter insertion; 3) using a 2% chlorhexidine preparation for skin antisepsis; 4) avoiding routine replacement of central venous catheters as a strategy to prevent infection; and 5) using antiseptic/antibiotic impregnated short-term central venous catheters if the rate of infection is high despite adherence to other strategies (ie, education and training, maximal sterile barrier precautions, and 2% chlorhexidine for skin antisepsis). These guidelines also identify performance indicators that can be used locally by health-care institutions or organizations to monitor their success in implementing these evidence-based recommendations.

The importance of evaluating product dispensers when selecting alcohol-based handrubs

BACKGROUND

To promote improved hand hygiene among personnel, a hospital installed dispensers for an alcohol-based hand rinse throughout the facility. Soon after installation, dispensers began to malfunction and continued to do so despite efforts to rectify the problem.

METHODS

Sixteen months after installation, dispensers in all patient rooms were examined, and surveyors recorded the condition of dispensers, the number of times the dispenser lever was pressed to obtain product, how the product was delivered onto the hand, and a qualitative estimate of the volume delivered.

RESULTS

Of 166 dispensers, 2% were broken, 7% had no product container, 5% had an empty product container, 9% contained product but were totally obstructed, and 77% were functional. Of the 128 functional dispensers, 65% delivered product after a single stroke of the lever, 13% after 2 strokes, 9% after 3 strokes, and 13% after 4 or more strokes. Seventeen percent delivered a small volume onto the hand, and 16% squirted the product onto the wall or floor.

CONCLUSION

Evaluation of alcohol-based handrubs should consider not only product characteristics, user acceptability, skin tolerance, and cost but also the design and function of the dispensers that will ultimately be installed.

Can alcohol hand rubs increase compliance with hand hygiene?

A review of the literature indicates that alcohol hand rubs reduce microbial load, are less irritant to the skin of healthcare workers, and are more easily accessible than conventional methods of hand hygiene. The review also indicates that using alcohol hand rub increases compliance to hand hygiene guideline rates by 25%. This study examines whether making alcohol hand rubs readily available to healthcare workers will increase and maintain compliance with hand hygiene protocols and guidelines, thereby reducing nosocomial infection, or whether the methods of staff education on the use and benefits of products and other interventions need to be examined.

Infection in the intensive care unit: prevention strategies

PURPOSE OF THE REVIEW

Nosocomial infections remain among the most common treatment complications, particularly in intensive care unit patients. In many countries antibiotic resistance is increasingly hampering treatment of these infections. Preventive strategies have therefore become more important and have been directed both against the development of specific infections and against the spread of antibiotic-resistant pathogens. The present review addresses recent data on the latter issue. In particular, we discuss the first approaches to use mathematical modelling as a tool to analyse and guide strategies to prevent infection, and the effects of antibiotic cycling.

RECENT FINDINGS

Several mathematical models to address the dynamics of pathogen transmission in hospital settings have been developed. One of the models may allow quantification of the effects of different strategies to prevent infection in intensive care units, and another may be used to determine the relative importance of different colonization routes, without the need for expensive genotyping methods. The results of the first prospective studies on antibiotic cycling are inconclusive, and again mathematical modelling may help to provide testable hypotheses for such interventions. Finally, recent studies have shown that alcohol-based hand rubs are better than hand washing with soap and water for most hand disinfection purposes.

SUMMARY

The first results of use of mathematical modelling to guide infection control strategies should be subjected to prospective, empirical testing in order to determine their clinical usefulness. More rigorously designed studies are needed to determine the benefits of antibiotic cycling strategies. Hands should be disinfected with alcohol-based hand rubs, which should be available at each bedside.

The impact of alcohol hand sanitizer use on infection rates in an extended care facility

BACKGROUND

Nosocomial infections are a major problem in health care facilities, resulting in extended durations of care and substantial morbidity. Since alcohol gel hand sanitizers combine high immediate antimicrobial efficacy with ease of use, this study was carried out to determine the effect of the use of alcohol gel hand sanitizer by caregivers on infection types and rates in an extended care facility.

METHOD

Infection rate and type data were collected in a 275-bed extended care facility for 34 months (July 1997 to May 2000), during which an alcohol gel hand sanitizer was used by the caregivers in 2 units of the facility.

RESULTS

The primary infection types found were urinary tract with Foley catheter, respiratory tract, and wound infections. Comparison of the infection types and rates for the units where hand sanitizer was used with those for the control units where the hand sanitizer was not used showed a 30.4% decrease in infection rates for the 34-month period in the units where hand sanitizer was used.

CONCLUSION

This study indicates that use of an alcohol gel hand sanitizer can decrease infection rates and provide an additional tool for an effective infection control program.

Scrubbing for cutaneous procedures can be hazardous

Office-based minor cutaneous surgery is a service provided by many medical practitioners. In New South Wales, Australia, it is a legal requirement for practitioners to surgically scrub before donning sterile gloves for all forms of invasive surgery, including minor cutaneous procedures. Frequent scrubbing causes altered skin barrier function, irritant dermatitis and a potential risk of latex sensitization. These adverse effects are associated with significant morbidity and cost. Better tolerated alternatives, including alcohol-based hand rubs, should be considered in preference to traditional surgical scrubs in order to reduce these occupational risks for minor proceduralists. Well-controlled, prospective studies should explore what extent of hand washing is necessary for donning sterile gloves for minor cutaneous surgery.

Methods for evaluating changes in skin condition due to the effects of antimicrobial hand cleansers: two studies comparing a new waterless chlorhexidine gluconate/ethanol-emollient antiseptic preparation with a conventional water-applied product

BACKGROUND

Hand-cleansing products that are milder to the skin of health care personnel are being developed, but the available methodologies to appropriately evaluate these products and quantify differences are not generally being applied in well-controlled studies.

METHODS

Two randomized, blinded, bilateral comparison studies evaluated skin condition during use of 2 antiseptic hand preparation products: a new 1% chlorhexidine gluconate (CHG)/61% wt/wt ethanol antiseptic hand preparation in a unique emollient system for waterless/brushless application and a conventional 4% CHG antimicrobial product that is applied with water and a scrub brush. Trained technicians applied treatments 6 times (for a surgical scrub study) or 24 times (for a personnel handwash study) daily to the hands of healthy volunteers during 5 days of controlled washing. An expert grader evaluated skin for dryness, erythema, and roughness. Subjects completed a self-assessment questionnaire on skin condition. Transepidermal water loss was measured by an evaporimeter, and the skin surface hydration level was measured by an electrical conductance meter.

RESULTS

Fifty-eight subjects were enrolled in the 2 studies and received both treatments. In general, skin treated with the waterless CHG/ethanol product scored significantly (P <.004) better on evaluations of visual dryness and erythema and showed greater improvement in the level of hydration (P <.003). In the health care personnel handwash study, transepidermal water loss was less than that for skin treated with the conventional CHG product (P <.002). Subject assessments showed similar results (total score, P <.007).

CONCLUSIONS

All 3 approaches of expert grader evaluation, subject assessment, and instrumentation were in concordance, demonstrating that the waterless CHG/ethanol product was gentler to skin than the conventional CHG product.

Is it time for brushless scrubbing with an alcohol-based agent?

The practice of surgical scrubbing in perioperative settings is changing rapidly. This article presents information about eliminating the traditional scrub brush technique and using an alcohol formulation for surgical hand scrubs. Also covered are antimicrobial agents, relevant US Food and Drug Administration classifications, skin and fingernail care, and implementation of changes. The article challenges surgical team members to evaluate a new and different approach to surgical hand scrubbing.

Irritancy of the skin disinfectant n-propanol

Hand disinfection with short-chain aliphatic alcohols, so-called "rub-ins" is the method of choice for cross-infection prevention in health care environments, but their irritant potential is not well known. Skin tolerance is a major compliance factor, and a high proportion of health care workers suffer from low-grade irritant contact dermatitis. Therefore, assessment of the irritancy of the skin disinfectant n-propanol 60%, and comparative 100% and 0% solutions, was performed in the setting of experimental low-grade ICD. ICD was induced by overnight patch exposure to H2O, and to 0.3% sodium dodecyl sulfate (SDS), in 12 probands, followed by repeated open exposure to the test substances. Outcome variables were transepidermal water loss (TEWL), and skin surface capacitance. On skin sites pre-irritated by SDS, all n-propanol concentrations (100%, 60%, 0%) increased TEWL. However, a clear divergence appeared between pure n-propanol, and the lower concentrations. In contrast to pure n-propanol, n-propanol 60% and 0% had no significant effect on TEWL on H2O-pre-irritated skin sites. Capacitance of pre-irritated skin sites was increased by exposure to H2O-containing n-propanol solutions (60% and 0%). These results show a clear difference between the irritant potential of n-propanol 100% on one side, and n-propanol 60% and 0% on the other side. The level of pre-existent skin irritation is a pertinent factor in susceptibility to irritation, as the irritant potential of n-propanol 60%, the concentration used in daily practice, and n-propanol 0% (water) became significant only on detergent-irritated skin. Thus, preventive skin care may be a constructive approach in increasing tolerance of modern hand disinfection practices.

Handwashing compliance in a French university hospital: new perspective with the introduction of hand-rubbing with a waterless alcohol-based solution

The baseline compliance with handwashing in a French university hospital was as low as the compliance rates reported in other countries, i.e., less than 50%. By introducing the use of hand-rubbing with an alcoholic solution, as a substitution method for both handwashing with soap and handwashing with an antiseptic agent, we significantly improved hand-cleansing compliance. Despite these encouraging results, mainly due to the accessibility of these non-aqueous products, three major obstacles remain before a wide acceptance by healthcare workers: distrust in terms of efficacy, distrust in terms of skin tolerance and lack of knowledge on hand-cleansing indications.

Nosocomial transmission of antibiotic-resistant microorganisms

The spread of nosocomially acquired, antibiotic-resistant microorganisms has grown dramatically over the past 20 years and has increasingly attracted the attention of academic inquiry. This article reviews recent epidemiological data about the trends and patterns of nosocomial transmission, presents clinical studies investigating mechanisms of cross-transmission, and discusses recent literature on preventive strategies aimed at reducing hand-carriage of antibiotic-resistant pathogens.

Compliance with hand disinfection and its impact on hospital-acquired infections

Hand hygiene prevents cross-infection in hospitals, but adherence to guidelines is poor among healthcare workers. Although some interventions to improve compliance have been successful, none had achieved lasting improvement until very recently. Reasons for non-compliance with recommendations occur at individual, group and institutional levels. The complexity of the process of behavioural change would suggest that the application of multimodal, multidisciplinary strategies are necessary. Both easy access to hand hygiene in a timely fashion and skin protection appear necessary prerequisites for satisfactory hand hygiene behaviour. Alcohol-based hand-rub may be superior to traditional handwashing as it requires less time, acts faster, irritates hands less often, and recently proved significantly to contribute to sustained improvement in compliance associated with decreased infection rates. This paper reviews barriers to appropriate hand hygiene and describes the results of the first successful experience of sustained hand hygiene promotion and its effectiveness on hospital-acquired infection.