Air and surface contamination patterns of meticillin-resistant Staphylococcus aureus on eight acute hospital wards.

BACKGROUND: Meticillin-resistant Staphylococcus aureus (MRSA) can be recovered from hospital air and from environmental surfaces. This poses a potential risk of transmission to patients. AIM: To investigate associations between MRSA isolates recovered from air and environmental surfaces with those from patients when undertaking extensive patient and environmental sampling. METHODS: This was a prospective observational study of patients and their environment in eight wards of a 700-bed tertiary care hospital during 2010 and 2011. Sampling of patients, air and surfaces was carried out on all ward bays, with more extended environmental sampling in ward high-dependency bays and at particular times of the day. The genetic relatedness of isolates was determined by DNA microarray profiling and spa typing. FINDINGS: MRSA was recovered from 30/706 (4.3%) patients and from 19/132 (14.4%) air samples. On 9/132 (6.8%) occasions both patient and air samples yielded MRSA. In 32 high-dependency bays, MRSA was recovered from 12/161 (7.4%) patients, 8/32 (25%) air samples, and 21/644 (3.3%) environmental surface samples. On 10/132 (7.6%) occasions, MRSA was isolated from air in the absence of MRSA-positive patients. Patient demographic data combined with spa typing and DNA microarray profiling revealed four likely transmission clusters, where patient and environmental isolates were deemed to be very closely related. CONCLUSION: Air sampling yielded MRSA on frequent occasions, especially in high-dependency bays. Environmental and air sampling combined with patient demographic data, spa typing and DNA microarray profiling indicated the presence of clusters that were not otherwise apparent.

"It's a hidden issue": exploring the experiences of women with HIV-associated neurocognitive challenges using a disability framework.

PURPOSE: To use the World Health Organization's International Classification of Functioning, Disability and Health (ICF) to explore the experiences of women living with self-identified HIV-associated neurocognitive challenges. METHOD: This interpretive, qualitative study involved key informant interviews with 16 women with self-identified HIV-associated neurocognitive challenges. Data were collected through 60-90 min, in-depth, semi-structured interviews. Thematic analysis was performed using an inductive approach. Theoretical analysis then used the ICF to reconceptualize the data using a disability lens. RESULTS: Participants perceived impairments (e.g. memory loss, difficulty multi-tasking) and participation restrictions (e.g. parenting, work roles) resulting from their neurocognitive challenges as having a larger impact on their daily lives than activity limitations (e.g. difficulty with chores). Participants held contrasting views about parenting: women with children drew strength from parenting whereas women without children worried that parenting could compromise their health. Participation in work and volunteering roles was viewed as integral to managing neurocognitive challenges and health overall. CONCLUSIONS: Conceptualizing neurocognitive challenges through a disability lens focuses attention on how impairments interact with other realities in these women's lives. This exploratory study reveals the need for future research exploring perceptions among people living with HIV-associated neurocognitive challenges with attention to aging and among other vulnerable groups.

Transmission of endemic ST22-MRSA-IV on four acute hospital wards investigated using a combination of spa, dru and pulsed-field gel electrophoresis typing.

The transmission of meticillin-resistant Staphylococcus aureus (MRSA) between individual patients is difficult to track in institutions where MRSA is endemic. We investigated the transmission of MRSA where ST22-MRSA-IV is endemic on four wards using demographic data, patient and environmental screening, and molecular typing of isolates. A total of 939 patients were screened, 636 within 72 h of admission (on admission) and 303 >72 h after admission, and 1,252 environmental samples were obtained. Isolates were typed by spa, dru and pulsed-field gel electrophoresis (PFGE) typing. A composite dendrogram generated from the three sets of typing data was used to divide isolates into 'dendrogram groups' (DGs). Ten percent of patients (92/939) were MRSA-positive; 7 % (44/636) on admission and 16 % (48/303) >72 h after admission (p = 0.0007). MRSA was recovered from 5 % of environmental specimens (65/1,252). Most isolates from patients (97 %, 85/88) and the environment (97 %, 63/65) exhibited the ST22-MRSA-IV genotype. Four DGs (DG1, DG4, DG16 and DG17) accounted for 58 % of ST22-MRSA-IV isolates from patients. Epidemiological evidence suggested cross-transmission among 44/92 patients (48 %) but molecular typing confirmed probable cross-transmission in only 11 instances (13 %, 11/88), with the majority of cross-transmission (64 %; 7/11) occurring on one ward. In the setting of highly clonal endemic MRSA, the combination of local epidemiology, PFGE, spa and dru typing provided valuable insights into MRSA transmission.

Evaluation of vaporized hydrogen peroxide, Citrox and pH neutral Ecasol for decontamination of an enclosed area: a pilot study.

Hydrogen peroxide, Ecasol and Citrox aerosols were each tested for their ability to kill a range of nosocomial pathogens. Hydrogen peroxide had the broadest microbicidal activity but operational issues limit its use. Ecasol was effective against all micro-organisms, except Clostridium difficile, while Citrox aerosols were not effective against Gram-negative bacilli.

Evaluation of different methods to recover meticillin-resistant Staphylococcus aureus from hospital environmental surfaces.

The environment is implicated as a source of healthcare-associated infections (HAIs) and there is a need for evidence-based approaches to environmental sampling to assess cleanliness and improve infection prevention and control. We assessed, in vitro, different approaches to sampling the environment for meticillin-resistant Staphylococcus aureus (MRSA). In a laboratory-based investigation, the recovery of MRSA from two common hospital environments using six different sampling methods was evaluated, with a wild-type strain of MRSA. A 100 cm(2) section of mattress and a laboratory bench surface were contaminated with known inocula of MRSA. Bacteria were recovered by sampling at 30 min after inoculation, using either saline-moistened cotton swabs, neutralising buffer swabs, eSwabs or macrofoam swabs, which were all enriched in tryptone soya broth, or by sampling with direct contact plates or chromogenic 'sweep' plates. The sensitivity (i.e. the minimum number of bacteria inoculated on to a surface which subsequently produced a positive result) of each method was determined for each surface. The most sensitive methods were eSwabs and macrofoam swabs, requiring 6.1 × 10(-1) and 3.9 × 10(-1) MRSA/cm(2), respectively, to produce a positive result from the bench surface. The least sensitive swabbing method was saline-moistened cotton swabs, requiring 1.1 × 10(3) MRSA/cm(2) of mattress. The recovery of bacteria from environmental samples varies with the swabs and methodology used and negative culture results do not exclude a pathogen-free environment. Greater standardisation is required to facilitate the assessment of cleanliness of healthcare environments.

When are the hands of healthcare workers positive for methicillin-resistant Staphylococcus aureus?

Hand hygiene is a key component in reducing infection. There are few reports on the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) on healthcare workers' (HCWs') hands. The aim of this study was to establish whether HCWs' fingertips were contaminated with MRSA in a clinical hospital setting. The study was conducted in an acute tertiary referral hospital on four MRSA wards that were part of a larger research study on MRSA epidemiology and four other wards not included in the study. The fingertips from all categories of 523 HCWs were sampled on 822 occasions by the imprinting of fingertips on MRSA chromogenic agar plates. The type of hand hygiene agent used, if any, and the immediate prior activity of the HCW were recorded. Overall, 38/822 (5%) fingertips from 523 HCWs were MRSA-positive; 12/194 (6%) after clinical contact, 10/138 (10%) after contact with the patient's environment and 15/346 (4%) after no specific contact. MRSA was recovered on 2/61 (3%) occasions after use of alcohol hand rub, 2/35 (6%) after 4% chlorhexidine detergent, 7/210 (3%) hand washing with soap and water, and 27/493 (5%) when no hand hygiene had been performed. MRSA was recovered from HCWs on seven of the eight wards. MRSA was more frequently present on fingertips on the four non-study wards vs the four MRSA study wards [18/250 (7%), 3/201 (1%), respectively; P

Is it really clean? An evaluation of the efficacy of four methods for determining hospital cleanliness.

An important component of effective cleaning in hospitals involves monitoring the efficacy of the methods used. Generally the recommended tool for monitoring cleaning efficacy is visual assessments. In this study four methods to determine cleaning efficacy of hospital surfaces were compared, namely visual assessment, chemical (ATP) and microbiological methods, i.e. aerobic colony count (ACC) and the presence of meticillin-resistant Staphylococcus aureus. Respectively, 93.3%, 71.5%, 92.1% and 95.0% of visual, ATP, ACC and MRSA assessments were considered acceptable or 'clean' according to each test standard. Visual assessment alone did not always provide a meaningful measure of surface cleanliness or cleaning efficacy. The average ATP value from 120 swabs before cleaning was 612 relative light units (RLU) (range: 72-2575) and 375 RLU after cleaning (range: 106-1071); the accepted standard is 500 RLU. In a hospital setting with low microbiological counts, the use of chemical tests such as ATP may provide additional information of cleaning efficacy and ATP trends allow identification of environmental surfaces that require additional cleaning or cleaning schedule amendments.

The contribution of beds to healthcare-associated infection: the importance of adequate decontamination.

The hospital bed is comprised of different components, which pose a potential risk of infection for the patient if not adequately decontaminated. In the literature there are a number of descriptions of outbreaks or experimental investigations involving meticillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, Acinetobacter spp., and other pathogens. Often only the bedrail has been sampled during investigation of outbreaks, rather than more important potential reservoirs of infection, such as mattresses and pillows, which are in direct contact with patients. It is essential that these items and other bed components are adequately decontaminated to minimise the risk of cross-infection, but detailed advice on this aspect is often lacking in reports and official documents. Clear guidelines should be formulated, specifying the decontamination procedure for each component of the bed. In outbreaks, investigation should include an assessment of mattresses and pillow contamination as a critical aspect in outbreak management.

Implications of colonization of vancomycin-resistant enterococci (VRE) in renal dialysis patients. Learning to live with it?

Vancomycin-resistant enterococci (VRE) commonly colonize, but less frequently infect, debilitated patients, such as those on chronic renal dialysis. The emergence of VRE amongst our cohort of renal replacement therapy patients posed considerable challenges in our attempts to prevent spread. Although 60 of 451 (13%) patients became colonized, only two patients required systemic antibiotics for confirmed or suspected invasive infection. Mortality and inpatient stay was greater in VRE-positive compared with VRE-negative patients (50% versus 10%) and patients who were screened on three or more occasions were likely to remain positive (e.g. 56% of patients screened on six occasions were positive). The application of recommended guidelines for the control of VRE, however, severely disrupted our renal dialysis programme and therefore had to be abandoned. As patients on renal dialysis are more likely to acquire VRE, remain colonized, require antibiotics and require regular inpatient or outpatient care more frequently than other patients, control measures should be adapted to minimize spread but not disrupt important and essential medical services.

A cluster of leptospirosis cases in canoeists following a competition on the River Liffey.

On 6 November 2001, a possible case of leptospirosis was notified in a canoeist following a white-water event on the River Liffey. It emerged that a second race participant was also a possible case. An outbreak control team coordinated the epidemiological investigation, laboratory investigation, environmental assessment, communication and control measures. A cluster of six laboratory-confirmed cases of leptospirosis, serologically Leptospira interrogans serogroup Icterohaemorrhagiae was found. The attack rate was 9.2% (6/65). Fever, chills, red eyes and shortness of breath were significantly associated with being a confirmed case. Five cases were hospitalized. Swallowing more than one mouthful of water was associated with an increased risk of developing leptospirosis. Increased rainfall and release of hydroelectric water may have contributed to this outbreak. A multidisciplinary approach and use of the Internet and e-mail facilitated rapid and effective communication.

The epidemiology of infectious syphilis in the Republic of Ireland.

In response to the increasing numbers of syphilis cases reported among men having sex with men (MSM) in Dublin, an Outbreak Control Team (OCT) was set up in late 2000. The outbreak peaked in 2001 and had largely ceased by late 2003. An enhanced syphilis surveillance system was introduced to capture data from January 2000. Between January 2000 and December 2003, 547 cases of infectious syphilis were notified in Ireland (415 were MSM). Four per cent of cases were diagnosed with HIV and 15.4% of cases were diagnosed with at least one other STI (excluding HIV) within the previous 3 months. The mean number of contacts reported by male cases in the 3 months prior to diagnosis was 4 (range 0-8) for bisexual contacts and 6 for homosexual contacts (range 1-90). Thirty one per cent of MSM reported having had recent unprotected oral sex and 15.9% of MSM reported having had recent unprotected anal sex. Sixteen per cent of cases reported having had sex abroad in the three months prior to diagnosis. The results suggest that risky sexual behaviour contributed to the onward transmission of infection in Dublin. The outbreak in Dublin could be seen as part of a European-wide outbreak of syphilis. The rates of co-infection with HIV and syphilis in Ireland are comparable with rates reported from other centres. There is a need to improve surveillance systems in order to allow real time evaluation of interventions and ongoing monitoring of infection trends.

The epidemiology of infectious syphilis in the Republic of Ireland.

In response to the increasing numbers of syphilis cases reported among men having sex with men (MSM) in Dublin, an Outbreak Control Team (OCT) was set up in late 2000. The outbreak peaked in 2001 and had largely ceased by late 2003. An enhanced syphilis surveillance system was introduced to capture data from January 2000. Between January 2000 and December 2003, 547 cases of infectious syphilis were notified in Ireland (415 were MSM). Four per cent of cases were diagnosed with HIV and 15.4% of cases were diagnosed with at least one other STI (excluding HIV) within the previous 3 months. The mean number of contacts reported by male cases in the 3 months prior to diagnosis was 4 (range 0-8) for bisexual contacts and 6 for homosexual contacts (range 1-90). Thirty one per cent of MSM reported having had recent unprotected oral sex and 15.9% of MSM reported having had recent unprotected anal sex. Sixteen per cent of cases reported having had sex abroad in the three months prior to diagnosis. The results suggest that risky sexual behaviour contributed to the onward transmission of infection in Dublin. The outbreak in Dublin could be seen as part of a European-wide outbreak of syphilis. The rates of co-infection with HIV and syphilis in Ireland are comparable with rates reported from other centres. There is a need to improve surveillance systems in order to allow real time evaluation of interventions and ongoing monitoring of infection trends.

Investigation of an outbreak of gastroenteritis caused by Norwalk-like virus, using solid phase immune electron microscopy.

In February 1993, 95 persons (47 patients and 48 staff members) were affected by an hospital outbreak of viral gastroenteritis. Using direct electron microscopy (EM) the causative agent was identified as a small round structured virus. This was confirmed as a Norwalk-like virus using solid phase immune electron microscopy (SPIEM). Of 94 stool samples examined, 12 (13%) samples containing small round structured viruses (SRSV) were SPIEM positive for Norwalk-like virus. A further 25 (27%) samples contained small round featureless virus (SRFV) identified by direct EM and were negative on SPIEM. The illness was characterized by preceding influenza-like symptoms in 76% of cases followed by vomiting (76%), diarrhoea (79%) and abdominal pain (79%). One fatality was recorded. The outbreak lasted for 15 days, with a peak incidence of new cases amongst patients and staff occurring on day 5. It was controlled through a combination of ward closures, patient cohorting, suspension of duties for affected staff and disinfection procedures. Difficulties were encountered in the education of staff and in the implementation of environmental control measures. Screening of hospital catering services and a case control study, carried out among affected staff members, failed to identify a foodborne source. Consumption of tap water in the hospital was commoner among affected staff members than among controls, but this did not reach significance (P = 0.1).

Examining the care of patients with peripheral venous cannulas.

The purpose of this study was to examine nursing issues in the care of patients with peripheral venous cannulas (PVCs) with particular focus on duration of cannulation in order to minimize risk of infection. A tentative practice model evolved from this study. The research approach used involved qualitative methods utilizing grounded theory. Data analysis produced one tentative core category, 'effectiveness'. This allowed for the development of a 12-dimensional model explaining the nursing function against four interrelated models: development; practice; organizational support; effectiveness. Related to these four models were key professional aspects of 'autonomy-control' and 'knowledge-practice'. Interpretative findings from the study were plotted against this model, giving a graphic representation and highlighting strengths and weaknesses of nursing practice. Aspects requiring improvement included: PVC care as a syllabus subject; nursing practice; autonomy and control issues; shared responsibility problems; documentation systems; goal setting; outcomes. The policy, nurses' knowledge of PVC care and identification of critical issues were considered satisfactory. The model incorporates 12 important dimensions associated with effective practice that can be applied to nursing at different levels - clinical practice, education, management - and to other disciplines, providing a framework for narrowing the theory-practice gap and improving patient care.

Suction apparatus and the suctioning procedure: reducing the infection risks.

Serious infection has been related to the use of suction apparatus and to the suctioning procedure. Prevention of infection focuses on aseptic technique, handwashing, decontamination and sterilization of apparatus where appropriate. This article considers the infection risks arising from use of suction apparatus, the suctioning procedure and sets out recommendations for infection prevention.