Hand Hygiene

Benedetta Allegranzi

Andrew Stewardson

Didier Pittet

HISTORY OF HAND HYGIENE

Handwashing with soap and water has been considered a measure of personal hygiene for centuries (1,2), but the link between handwashing and the spread of disease has only been established in the last 200 years. In the mid-1800s, decades before the discoveries of Pasteur and Lister, studies by Ignaz Semmelweis in Vienna and Oliver Wendell Holmes in Boston established that hospital-acquired diseases were transmitted via the hands of healthcare workers (HCWs). In 1847, Semmelweis was appointed as a house officer in one of the two obstetric clinics located at the University of Vienna Allgemeine Krankenhaus (General Hospital). He observed that maternal mortality rates, mostly due to puerperal fever, were substantially higher in one clinic compared to the other (16% vs. 7%) (3). He also noted that physicians and medical students often went directly to the delivery suite after performing autopsies and had a disagreeable odor on their hands, despite handwashing with soap and water before entering the clinic. He hypothesized that “cadaverous particles” were transmitted via the hands of students and physicians and caused the puerperal fever. As a consequence, Semmelweis recommended that hands be scrubbed in a chlorinated lime solution before every patient contact and particularly after leaving the autopsy room. Following the implementation of this measure, the mortality rate dropped dramatically to 3% in the clinic most affected. This intervention represents the first evidence that cleansing heavily contaminated hands with an antiseptic agent can reduce nosocomial transmission of microorganisms more effectively than handwashing with plain soap and water. Unfortunately, both Holmes and Semmelweis failed to observe a sustained change in their colleagues’ behavior.

A prospective controlled trial conducted in a hospital nursery (4) and investigations conducted during the past 40 years have confirmed the critical role that contaminated HCWs’ hands play in the transmission of healthcare-associated pathogens (5,6). The 1980s represented a landmark in the evolution of concepts of hand hygiene in healthcare. The first national hand hygiene guidelines were published in the United States in the 1980s (7,8,9), followed by several others in more recent years in different countries. In 1995 and 1996, the US Centers for Disease Control and Prevention’s (CDC) Healthcare Infection Control Practices Advisory Committee (HICPAC) recommended that either an antimicrobial soap or a waterless antiseptic agent be used for cleansing hands upon leaving the rooms of patients with multidrug-resistant pathogens (10,11). More recently, the CDC/HICPAC guidelines issued in 2002 (12) and the World Health Organization (WHO) Guidelines on Hand Hygiene in Healthcare (6) have defined alcohol-based handrubbing, where available, as the standard of care for hand hygiene practices in healthcare settings, whereas handwashing is reserved for particular situations only (6) (Table 3.1).

DEFINITIONS

Hand hygiene is a general term referring to any action of hand cleansing. The purpose of performing hand hygiene during routine patient care is to remove microbial contamination acquired by recent contact with infected or colonized patients or with environmental sources and, in some cases, to remove organic matter from the hands. Hand hygiene during healthcare delivery can be performed either by handwashing or by handrubbing.

Standard handwashing with plain soap and water removes lipid and adhering dirt, soil, and various organic substances from the hands, but it has minimal antimicrobial activity.

Hygienic hand antisepsis is defined as the treatment of hands with either an antiseptic hand rub or an antimicrobial soap or detergent and water to reduce the transient microbial flora without necessarily affecting the resident skin flora (6).

Antiseptic hand rubs are available as different formulations (liquid, gels, foams) and bypass the need for an exogenous source of water and towels or other hand-drying devices. According to the CDC guidelines (12) and WHO recommendations (6), when an alcohol-based hand rub is available it should be used as the preferred means for routine hand hygiene in healthcare.

Indications for performing hand hygiene and for opting for handwashing rather than handrubbing are discussed below and listed in Table 3.1.

TRANSMISSION OF MICROORGANISMS AND HAND HYGIENE BEHAVIOR

A clear understanding of the process of hand-pathogen transmission is critical to successful education strategies, assessment of HCWs’ hand hygiene performance, and research. An evidence-based model of hand transmission was proposed by Pittet et al. and served as a basis for the recently reviewed recommendations on indications for hand hygiene action (5,6). According to this model, the transmission of healthcare-associated pathogens from one patient to another or within the same patient from one body site to another via HCWs’ hands requires five sequential steps (Figure 3.1). It is important

to recall that in addition to transfer of pathogens from the hospital environment or patient-to-patient transmission, pathogen transfer can occur within the same patient from a colonized area to a clean body site or onto an invasive medical device. Given that most healthcare-associated infections (HAIs) are of endogenous nature, this latter pathway of transmission by HCWs’ hands is of the utmost etiologic importance.

TABLE 3.1 Indications for Handwashing and Hand Antisepsis

Wash hands with soap and water when visibly dirty or contaminated with proteinaceous material, or visibly soiled with blood or other body fluids, or if exposure to potential spore-forming organisms is strongly suspected or proven (IB), or after using the restroom (II).
Preferably use an alcohol-based hand rub for routine hand antisepsis in all other clinical situations described in items (a) to (f) listed below if hands are not visibly soiled (IA). Alternatively, wash hands with soap and water (IB).
Perform hand hygiene:
1. before and after having direct contact with patients (IB);
2. after removing gloves (IB);
3. before handling an invasive device for patient care, regardless of whether or not gloves are used (IB);
4. after contact with body fluids or excretions, mucous membranes, nonintact skin, or wound dressings (IA);
5. if moving from a contaminated body site to a clean body site during patient care (IB);
6. after contact with inanimate objects (including medical equipment) in the immediate vicinity of the patient (IB).
Wash hands with either plain or antimicrobial soap and water or rub hands with an alcohol-based formulation before handling medication or preparing food (IB).
When alcohol-based hand rub is already used, do not use antimicrobial soap concomitantly (II).

Adapted from the WHO Guidelines for Hand Hygiene in Health Care. Geneva, Switzerland: World Health Organization; 2009.

Figure 3.1. The model for hand transmission of microbial pathogens. Step 1: Organisms present on patient skin or the inanimate environment. Both the patient skin and the inanimate environment harbor large amounts of organisms including multiresistant bacteria, fungi, and viruses. Step 2: Organism transfer on HCWs’ hands. Hand skin acquires transient flora by exposure to colonized objects, inanimate surfaces, and patients. Gloves do not provide complete protection against hand contamination. Step 3: Organism survival on hands. Hand colonization with transient flora as well as with potential pathogens progressively increases during patient care according to their differing capacity to survive on skin. Step 4: Defective hand hygiene results in hands remaining contaminated. Adequate (appropriate duration and full coverage of hand surfaces) and timely (when indicated) hand hygiene technique is essential for the effective removal of contamination and to prevent persistent colonization. Wearing rings and artificial fingernails increases the frequency of hand contamination and has been associated with infection outbreaks. Step 5: Contaminated hands cross-transmit organisms. Failure to practice hand hygiene between sequential hand-surface exposures results in HCWs’ hands acting as organism carriers ready to spread potentially harmful pathogens onto another surface. Once deposited on patients, the cross-transmitted organisms may establish either a carrier state or lead directly to infection.(Adapted from Pittet D, Allegranzi B, Sax H, et al. Evidence-based model for hand transmission during patient care and the role of improved practices. Lancet Infect Dis. 2006;6:641-652.)

Recent epidemiologic investigations on HCWs’ compliance with hand hygiene recommendations have revealed key findings. According to the literature, in the absence of hand hygiene promotion, compliance has been unacceptably poor in many countries worldwide with mean baseline rates ranging from 5% to 89% and an overall average of about 40% (reviewed in detail in (6) with selected subsequent references including (13,14,15,16,17)). Very low compliance rates have been reported especially in poorly resourced settings (18,19,20,21,22,23,24,25). The predictors of poor adherence to recommended hand hygiene measures during routine patient care have been identified (6), and include professional category (13,14,15,26,27), hospital ward (14,28,29), time of day/week (30,31), glove use (26,32,33,34,35), and type and intensity of patient care, defined either as the number of opportunities for hand hygiene per hour of patient care (Figure 3.2) or patient-to-nurse ratio (Table 3.2) (13,14,28). Moreover, hand hygiene compliance is frequently poorer before patient contact than after (6,14,26,31,36), although this is not always observed (29).

Perceived barriers to adherence with hand hygiene guidelines have been assessed or quantified in observational studies (6). Among others, they include skin irritation caused by hand hygiene agents (34), inaccessible hand hygiene supplies (13,15), interference with HCW-patient relationships, patient needs perceived as a priority over hand hygiene, forgetfulness, lack of knowledge of guidelines, insufficient time for hand hygiene (34), and high workload and understaffing (Table 3.2). Adherence may be better when patients are under contact precautions (15,37).

Figure 3.2. The relation between the number of opportunities for hand hygiene and compliance. (Reproduced with permission from Pittet D, Mourouga P, Perneger TV. Compliance with handwashing in a teaching hospital. Ann Int Med. 1999; 130:126-130.)

TABLE 3.2 Main Factors Influencing Adherence to Hand Hygiene Practices

INDIVIDUAL LEVEL:

Lack of education or experience
Being a physician, compared to other healthcare professionals
Lack of knowledge of guidelines
Being a refractory noncomplier
Skin irritation by hand hygiene agents

GROUP LEVEL:

Lack of education or lack of performance feedback
Working in critical care or in high-workload conditions
Downsizing or understaffing
Lack of encouragement or role model from key staff

INSTITUTIONAL LEVEL:

Lack of written guidelines
Lack of suitable hand hygiene agents
Lack of skin care promotion or agents
Lack of culture or tradition of compliance
Lack of administrative leadership, sanctions, rewards, or support

GOVERNMENTAL LEVEL:

Lack of awareness and commitment regarding the importance of healthcare-associated infection
Lack of specific regulations and policies on prevention of healthcare-associated infection
Lack of national guidelines on hand hygiene in healthcare
Lack of promotion of national or regional campaigns to improve hand hygiene in healthcare
Insufficient allocation of financial resources for this purpose

HAND ANTISEPSIS AGENTS

Antiseptic agents (both soap and hand rubs) contain an antimicrobial substance, which reduces or inhibits the growth of microorganisms on living tissues. The most popular agents are briefly described below and summarized in Table 3.3.

Amongst hand antisepsis agents, alcohols have the broadest spectrum of antimicrobial activity with excellent in vitro and in vivo activity against gram-positive and gram-negative bacteria (including multidrug-resistant pathogens such as methicillin-resistant Staphylococcus aureus [MRSA] and vancomycin-resistant Enterococci [VRE]), Mycobacterium tuberculosis, and a variety of fungi (38,39,40,41,42,43,44,45,46,47). Mycobacteria and fungi also are killed by iodophors, but less effectively by chlorhexidine, chloroxylenol, and hexachlorophene. Most enveloped (lipophilic) viruses, such as herpes simplex virus, HIV, influenza virus, respiratory syncytial virus, and vaccinia virus, are susceptible to alcohols, chlorhexidine, and iodophors (38,48,49,50,51,52,53,54,55,56,57). Other enveloped viruses (hepatitis B virus and probably hepatitis C virus) are somewhat less susceptible to alcohols, but are killed by concentrations as high as 60% to 70% (v/v) (58). In some in vivo studies, alcohols also showed some activity against a number of nonenveloped viruses (rotavirus, adenovirus, rhinovirus, hepatitis A virus, and enteroviruses) (59,60,61,62,63). In general, ethanol has greater activity against viruses than isopropanol (64). Iodophors, and to a minor extent chlorhexidine, also are active against some nonenveloped viruses. None of the listed antiseptic agents has activity against bacterial spores or protozoan oocysts. Iodophors are only slightly sporicidal, but at higher concentrations than the ones used in antiseptics (65).

TABLE 3.3 Preparations for Hand Hygiene

Agent	Gram-Positive Bacteria	Gram-Negative Bacteria	Mycobacteria	Fungi	Enveloped Virus	Nonenveloped Virus	Spores	Speed of Action	Residual Activity	Use
Alcohols	+++	+++	+++	+++	++	+	–	Fast	No	HR
Chlorhexidine	+++	++	+	+	++	+	–	Intermediate	Yes	HR, HW
Chloroxylenol	+++	+	+	+	+	+/-	–	Slow	Contradictory	HW
Hexachlorophene^a	+++	+	+	+	?	?	–	Slow	Yes	HW, but not recommended
Iodophors	+++	+++	++	++	++	++	+/-^b	Intermediate	Contradictory	HW
Quaternary ammonium compounds^c	++	+	+/-	+/-	+	?	–	Slow	No	HR, HW; seldom; + alcohols
Triclosan^d	+++	++	+/-	+/-^e	?	?	–	Intermediate	Yes	HW; seldom
HR, handrubbing; HW, handwashing
Activity: +++, excellent; ++, good, but does not include the entire bacterial spectrum; +, fair; +/-, controversial; -, no activity; ?, insufficient data.
^aBacteriostatic. ^bIn concentrations used in antiseptics, iodophors are not sporicidal. ^cBacteriostatic, fungistatic, and microbicidal at high concentrations. ^dMostly bacteriostatic. ^eActivity against Candida spp., but little activity against filamentous fungi.

Alcohols are the most frequently used antimicrobial component of hand rubs. Alcohol-based hand rubs are considered the most effective antiseptic agents for hand hygiene, and they generally contain either ethanol, isopropanol, or n-propanol, or a combination of two of these products. Alcohol solutions containing 60% to 80% (v/v) alcohol are most effective, with both higher and lower concentrations being less potent (39,40,66). Alcohols are more effective than plain soap, and in the vast majority of trials they reduced bacterial counts on hands to a greater extent than washing hands with soaps or detergents containing hexachlorophene, povidone-iodine, 4% chlorhexidine, or triclosan (67,68). Several forms of alcohol-based products are available, including rinses (low-viscosity solutions), gels, and foams. The efficacy of each product should be confirmed as this will vary according to its formulation and the concentration of its active components (6,69,70,71,72,73,74,75). The WHO-recommended alcohol-based formulations contain either ethanol (80% v/v) or isopropyl alcohol (75% v/v), and can be produced locally to reduce costs (6,21,76).

Chlorhexidine gluconate has been incorporated into a number of hand hygiene preparations. Aqueous or detergent formulations containing 0.5%, 0.75%, or 1% chlorhexidine are more effective than plain soap, but are less effective than antiseptic detergent preparations containing 2% and 4% chlorhexidine gluconate (77,78). Chlorhexidine’s immediate antimicrobial activity is slower than that of alcohols, but it has significant residual activity (77,78,79,80,81,82,83,84). Chlorhexidine resistance attributable to plasmid-borne qacA/B genes that code for multidrug efflux pumps is being increasingly reported, though the impact of this phenomenon on the effectiveness of hand hygiene products containing chlorhexidine is not well-defined (85,86,87,88).

Iodophors are composed of elemental iodine, iodide or triiodide, and a polymer carrier of high molecular weight, such as polyvinyl pyrrolidone (povidone) and ethoxylated nonionic detergents (poloxamers) (52,89). Their persistent antimicrobial activity is controversial. Most iodophor preparations used for hand hygiene contain 7.5% to 10% povidone-iodine.

Chloroxylenol has been widely used in antimicrobial soaps and as a preservative in cosmetics and other products. It has good in vitro activity against gram-positive organisms and fair activity against gram-negative bacteria, Mycobacteria, and some viruses (1,90,91); in particular, the activity against Pseudomonas aeruginosa is limited. Chloroxylenol is considered to be less rapidly active than chlorhexidine gluconate or iodophors, and its residual activity is less pronounced than that of chlorhexidine (90,91).

Hexachlorophene is a bisphenol contained in emulsions used for hygienic handwashing and for patient bathing. It has residual activity for several hours after use and a cumulative effect (1,92,93,94). Because of its high rates of dermal absorption and subsequent toxic effects, including neurotoxicity (95), the agent is classified by the U.S. Food and Drug Administration (FDA) as not safe and effective for use as an antiseptic agent for handwashing and has been banned worldwide (64,96,97).

Quaternary ammonium compounds belong to a large group; alkyl benzalkonium chlorides have been the most widely used antiseptics. They are primarily bacteriostatic and fungistatic, although microbicidal at high concentrations against some organisms (1). They are more active against gram-positive bacteria than against gram-negative bacilli, and have relatively weak activity against Mycobacteria and fungi and greater activity against lipophilic viruses.

Triclosan is a nonionic, colorless substance that has antimicrobial activity at concentrations ranging from 0.2% to 2.0%, but tends to be bacteriostatic (1). Like chlorhexidine, triclosan has persistent activity on the skin. According to the FDA, the available data are insufficient to classify it as safe and effective for hand antisepsis (96).

Every new formulation for hand antisepsis should be tested for its antimicrobial efficacy to demonstrate that it has superior efficacy over normal soap or meets an agreed performance standard. The most appropriate method is to artificially contaminate volunteers’ hands with the test organism before applying the test formulation. In Europe, the most commonly used test methods are those of the European Committee for Standardization (CEN): EN 1499 (98) for antiseptic soaps and EN 1500 (99) for hand rubs. These use a randomized, cross-over design and compare the product with a standardized reference agent. In the United States, antiseptics are regulated by the FDA (96), which refers to the standards of the American Society for Testing and Materials (ASTM). The most frequently used method for testing hand-washing and handrubbing agents is the ASTM E-1174 (100). The shortcomings of current test methods are discussed in detail elsewhere (6,73).

INDICATIONS FOR HAND HYGIENE DURING HEALTHCARE

Effective hand hygiene should remove transient flora on HCWs’ hands at critical moments during care activity with the clear objective to prevent cross-transmission of potentially harmful organisms and infection. A set of indications for hand hygiene has been established according to scientific evidence and is congruent with the model of transmission (see above). These indications are listed in the most recent international guidelines and graded according to supporting evidence (Table 3.1) (6,101). To support their application at the point of care, a new concept was developed by WHO on the basis of expert advice and scientific evidence that condenses these indications into five moments when hand hygiene is required (6,102). This approach proposes a unified vision for HCWs, trainers, and observers to minimize interindividual variation and facilitate training, understanding, monitoring, and reporting of hand hygiene indications, and achieving best practices. According to this concept, HCWs are requested to clean their hands (a) before touching a patient; (b) before clean/aseptic procedures; (c) after body fluid exposure/risk; (d) after touching a patient; and (e) after touching patient surroundings. This concept has been integrated into the various WHO tools for the implementation of the WHO Guidelines (103) and has been adopted worldwide, including in national hand hygiene guidelines (Figure 3.3).

According to the model of transmission, hand hygiene before a patient contact or an invasive procedure is aimed at protecting the patient. In contrast, hand hygiene after tasks or contact with patients and their immediate surroundings serves to protect the HCW against colonization and infection and to prevent pathogen spread to the environment. As discussed above, HCWs more often comply with the indications after a patient contact or after a healthcare task.

Figure 3.3. “My five moments for hand hygiene.” (Reproduced with permission from Sax H, Allegranzi B, Uckay I, et al. “My five moments for hand hygiene”: a user-centred design approach to understand, train, monitor and report hand hygiene. J Hosp Infect. 2007;67:9-21.)

For practical purposes, it is important to recognize that two or more of the listed indications might occur simultaneously during a sequence of care requiring only a single hand hygiene action. The guidelines also describe optimal techniques for handrubbing and handwashing, and specify that the latter be reserved only for situations where hands are visibly soiled, where transmission of spores is strongly suspected or proven, and after using the restroom (6) (Table 3.1).

Hand hygiene should be performed after glove removal because wearing gloves does not completely prevent hand contamination (6,26,104,105,106,107). Moreover, hand hygiene should be performed when an indication occurs, regardless of whether gloves are worn or not (6,12).

IMPACT OF HAND HYGIENE PROMOTION

The positive effect of hand hygiene promotion, in particular through multimodal strategies, is usually demonstrated by an increase in hand hygiene compliance, which is meant to reflect actual HCWs’ practices at the point of care. Over the past two decades, several studies have demonstrated the effectiveness of such strategies on improving this process indicator, mostly based on a multimodal approach (6,21,27,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126).

It is evident that the most valuable method to demonstrate the impact of hand hygiene improvement is to detect a significant reduction of HAI rates in the study-intervention setting. Ideally, this key research question should be investigated through controlled (cluster) randomized studies focusing only on hand hygiene interventions and adjusting for confounders. For several reasons, particularly ethical, most published studies on this topic are observational, before-after intervention investigations. Despite this lower quality design, many studies focusing on hand hygiene as the single new intervention implemented during the study period demonstrated a temporal relation between improved hand hygiene practices and reduced infection rates (Table 3.4), and several reported a sustained effect over a prolonged period of time (108,109,110,111,112,113,114,127,128,129,130,131,132).

In addition, over the past decade, an increasing number of studies have investigated the temporal association between hand hygiene product consumption and HAIs, particularly focusing on alcohol-based hand rub and MRSA bacteremia (111,112,132,133,134,135

Only gold members can continue reading. Log In or Register to continue