John M. Boyce

SHEA Guideline for Preventing Nosocomial Transmission of Multidrug-Resistant Strains of Staphylococcus aureus and Enterococcus

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 sur veillance 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 (Infect Control Hosp Epidemiol 2003;24:362-386).

Emergence and resurgence of meticillin-resistant Staphylococcus aureus as a public-health threat.

Staphylococcus aureus is a gram-positive bacterium that colonises the skin and is present in the anterior nares in about 25-30% of healthy people. Dependent on its intrinsic virulence or the ability of the host to contain its opportunistic behaviour, S aureus can cause a range of diseases in man. The bacterium readily acquires resistance against all classes of antibiotics by one of two distinct mechanisms: mutation of an existing bacterial gene or horizontal transfer of a resistance gene from another bacterium. Several mobile genetic elements carrying exogenous antibiotic resistance genes might mediate resistance acquisition. Of all the resistance traits S aureus has acquired since the introduction of antimicrobial chemotherapy in the 1930s, meticillin resistance is clinically the most important, since a single genetic element confers resistance to the most commonly prescribed class of antimicrobials--the beta-lactam antibiotics, which include penicillins, cephalosporins, and carbapenems.

ENVIRONMENTAL CONTAMINATION DUE TO METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS: POSSIBLE INFECTION CONTROL IMPLICATIONS

OBJECTIVE To study the possible role of contaminated environmental surfaces as a reservoir of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals. DESIGN A prospective culture survey of inanimate objects in the rooms of patients with MRSA. SETTING A 200-bed university-affiliated teaching hospital. PATIENTS Thirty-eight consecutive patients colonized or infected with MRSA. Patients represented endemic MRSA cases. RESULTS Ninety-six (27%) of 350 surfaces sampled in the rooms of affected patients were contaminated with MRSA. When patients had MRSA in a wound or urine, 36% of surfaces were contaminated. In contrast, when MRSA was isolated from other body sites, only 6% of surfaces were contaminated (odds ratio, 8.8; 95% confidence interval, 3.7-25.5; P < .0001). Environmental contamination occurred in the rooms of 73% of infected patients and 69% of colonized patients. Frequently contaminated objects included the floor, bed linens, the patients gown, overbed tables, and blood pressure cuffs. Sixty-five percent of nurses who had performed morning patient-care activities on patients with MRSA in a wound or urine contaminated their nursing uniforms or gowns with MRSA. Forty-two percent of personnel who had no direct contact with such patients, but had touched contaminated surfaces, contaminated their gloves with MRSA. CONCLUSIONS We concluded that inanimate surfaces near affected patients commonly become contaminated with MRSA and that the frequency of contamination is affected by the body site at which patients are colonized or infected. That personnel may contaminate their gloves (or possibly their hands) by touching such surfaces suggests that contaminated environmental surfaces may serve as a reservoir of MRSA in hospitals.

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.

Environmental contamination makes an important contribution to hospital infection.

Meticillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) are capable of surviving for days to weeks on environmental surfaces in healthcare facilities. Environmental surfaces frequently touched by healthcare workers are commonly contaminated in the rooms of patients colonized or infected with MRSA or VRE. A number of studies have documented that healthcare workers may contaminate their hands or gloves by touching contaminated environmental surfaces, and that hands or gloves become contaminated with numbers of organisms that are likely to result in transmission to patients. Pathogens may also be transferred directly from contaminated surfaces to susceptible patients. There is an increasing body of evidence that cleaning or disinfection of the environment can reduce transmission of healthcare-associated pathogens. Because routine cleaning of equipment items and other high-touch surfaces does not always remove pathogens from contaminated surfaces, improved methods of disinfecting the hospital environment are needed. Preliminary studies suggest that hydrogen peroxide vapour technology deserves further evaluation as a method for decontamination of the environment in healthcare settings.

The World Health Organization Guidelines on Hand Hygiene in Health Care and their consensus recommendations

The World Health Organizations Guidelines on Hand Hygiene in Health Care have been issued by WHO Patient Safety on 5 May 2009 on the occasion of the launch of the Save Lives: Clean Your Hands initiative. The Guidelines represent the contribution of more than 100 international experts and provide a comprehensive overview of essential aspects of hand hygiene in health care, evidence- and consensus-based recommendations, and lessons learned from testing their Advanced Draft and related implementation tools.

Hand hygiene and patient care: pursuing the Semmelweis legacy

Summary Modern medicine still has to contend with the major problem of infections resulting from patient care. Despite considerable evidence that appropriate hand hygiene is the leading measure to reduce cross-infection, compliance with recommendations remains notoriously low among healthcare workers. In high-demand situations, such as in most critical-care units, or at times of overcrowding or understaffing, promoting hand cleansing with an alcohol-based handrub solution seems to be the most practical means of improving compliance. It requires less time, acts faster, irritates hands less often, and is superior to traditional handwashing or medicated hand antiseptic agents. Furthermore, it was used in the only programme that reported a sustained improvement in hand-hygiene compliance associated with decreased infection rates. Although easy access to fast-acting hand-hygiene agents is the main tool of any campaign to obtain sustained improvement with hand-hygiene practices, a multidisciplinary approach is necessary to produce behavioural change.

Methicillin-Resistant Staphylococcus aureus in Hospitals and Long-Term Care Facilities: Microbiology, Epidemiology, and Preventive Measures

Strains of methicillin-resistant Staphylococcus aureus (MRSA) have become increasingly common in the United States and in many other countries since 1975. Although MRSA was recovered primarily in university and federal hospitals in this country during the late 1970s, these organisms are being encountered with increasing frequency in all types of hospitals, especially in the eastern half of the United States. Although there is a paucity of information available on the prevalence of MRSA in long-term care facilities, a few reports suggest that MRSA is also seen frequently in these settings. Because colonized patients are frequently transferred between hospitals and long-term care facilities, a continuing circuit of MRSA transmission occurs in areas where these organisms are prevalent. MRSA prevalence rates vary widely by locale and by type and size of hospital. In some geographic areas, the prevalence remains low, whereas in other areas, from 10% to 50% of all S aureus isolates recovered from patients in large medical centers are MRSA. Even within a given city, MRSA prevalence rates may vary widely among acute care hospitals.

Impact of Hydrogen Peroxide Vapor Room Decontamination on Clostridium difficile Environmental Contamination and Transmission in a Healthcare Setting

OBJECTIVE To determine whether hydrogen peroxide vapor (HPV) decontamination can reduce environmental contamination with and nosocomial transmission of Clostridium difficile. DESIGN A prospective before-after intervention study. SETTING A hospital affected by an epidemic strain of C. difficile. INTERVENTION Intensive HPV decontamination of 5 high-incidence wards followed by hospital-wide decontamination of rooms vacated by patients with C. difficile-associated disease (CDAD). The preintervention period was June 2004 through March 2005, and the intervention period was June 2005 through March 2006. RESULTS Eleven (25.6%) of 43 cultures of samples collected by sponge from surfaces before HPV decontamination yielded C. difficile, compared with 0 of 37 cultures of samples obtained after HPV decontamination (P < .001). On 5 high-incidence wards, the incidence of nosocomial CDAD was significantly lower during the intervention period than during the preintervention period (1.28 vs 2.28 cases per 1,000 patient-days; P = .047). The hospital-wide CDAD incidence was lower during the intervention period than during the preintervention period (0.84 vs 1.36 cases per 1,000 patient-days; P = .26). In an analysis limited to months in which the epidemic strain was present during both the preintervention and the intervention periods, CDAD incidence was significantly lower during the intervention period than during the preintervention period (0.88 vs 1.89 cases per 1,000 patient-days; P = .047). CONCLUSIONS HPV decontamination was efficacious in eradicating C. difficile from contaminated surfaces. Further studies of the impact of HPV decontamination on nosocomial transmission of C. difficile are warranted.

MRSA patients: proven methods to treat colonization and infection.

Methicillin-resistant Staphylococcus aureus (MRSA) infections continue to cause serious nosocomial infections in many hospitals. Measures used to control the spread of these infections include ongoing laboratory-based surveillance, placing colonized and infected patients in isolation, use of barrier precautions and handwashing and hand antisepsis. Culturing hospitalized patients at high risk of acquiring MRSA can facilitate detection and isolation of colonized patients. Eradicating MRSA nasal colonization among affected patients and healthcare personnel has also been as a control measure, with variable success. Eradicating MRSA nasal carriage from epidemiologically-implicated healthcare workers has been used on a number of occasions to control outbreaks. Attempts to eradicate MRSA colonization among affected patients has proven difficult. Of more than 40 different decolonization regimens that have been tested during the last 60 years, topical intranasal application of mupirocin ointment has proven to be the most effective. However, intranasal application of mupirocin has limited effectiveness in eradicating colonization in patients who carry the organism at multiple body sites. Furthermore, because decolonization of patients has virtually always been used in combination with other control measures, its efficacy has been difficult to determine. Because MRSA is transmitted primarily on the hands of healthcare workers, greater emphasis should be given to improving hand hygiene practices among health personnel. For patients infected with MRSA, vancomycin remains a drug of choice.