Use of genome sequencing to identify hepatitis C virus transmission in a renal healthcare setting.

BACKGROUND: Hepatitis C virus (HCV) infection is a major health burden worldwide. A patient with no history of HCV infection while on a renal unit was found to seroconvert to HCV. AIM: To report the use of sequencing to postulate how transmission of HCV occurred in a healthcare setting, and how this guided our outbreak investigation. FINDINGS: Based on infection control inspections the transmission event was surmised to be due to ward environmental contamination with blood and subsequent inoculation from intravenous interventions on the patient acquiring HCV. We discuss the interventions put in place in response to the outbreak investigation findings. CONCLUSION: Sequencing of healthcare-acquired HCV infections should be undertaken as routine practice in outbreak investigations.

Decontamination of heater-cooler units associated with contamination by atypical mycobacteria.

BACKGROUND: Non-tuberculosis mycobacteria such as Mycobacterium chimaera are found widely in hospital water systems. Invasive M. chimaera infections have recently been attributed to heater-cooler units (HCUs) of cardiopulmonary bypass equipment. AIM: To assess the extent of microbiological contamination within the HCUs and to inform decontamination strategies for reducing the microbial load. METHODS: Water samples taken from HCUs used at University Hospitals Birmingham for cardiopulmonary bypass surgery were sampled to determine the number of micro-organisms by membrane filtration. Various decontamination processes were used throughout the study, all based on the manufacturer's guidance. FINDINGS: Total viable counts >300cfu per 100mL containing a wide variety of micro-organisms were obtained from water inside the HCUs. Working with the manufacturers, we significantly reduced the microbial load of the water within the HCUs by removing the internal tubing soiled with biofilm followed by a weekly decontamination regimen with peracetic acid. CONCLUSION: A decontamination cycle including an initial replacement of internal tubing with weekly microbiological water samples is required to maintain the water quality within HCUs at an acceptable level.

Environmental decontamination following occupancy of a burns patient with multiple carbapenemase-producing organisms.

Over the last decade, carbapenemase-producing organisms (CPOs) have spread worldwide, becoming a major public health concern. This article reports the authors' experience in dealing with a burns patient infected with CPOs, and the decontamination methods employed to render a burns shock room safe for re-use. The shock room was cleaned after being vacated, but environmental sampling cultured multiple CPOs. A second decontamination was undertaken comprising a detergent, steam and hypochlorite clean followed by hydrogen peroxide misting, and no CPOs were cultured after subsequent environmental sampling. A burns patient harbouring CPOs contaminates the surroundings heavily, so standard cleaning is insufficient to reduce the environmental bioburden.

Epidemiology, clinical characteristics, and outcome of candidemia: experience in a tertiary referral center in the UK.

OBJECTIVES: To review the epidemiology of candidemia in a UK tertiary referral center. METHODS: Clinical and laboratory data from patients with candidemia were collected prospectively from October 1, 2005 to June 30, 2008 (a 33-month period). RESULTS: A total of 107 episodes were identified. The incidence was 10.9 episodes/100 000 bed-days. The most common predisposing factors were the use of broad-spectrum antibiotics (92%), the presence of an intravascular device (IVD) (82%), admission to an intensive care unit (ICU) (51%), and recent surgery (50%). Non-Candida albicans species accounted for 58% of the episodes, which is higher than the percentage reported from other UK centers. C. albicans was the most common species, accounting for 43% of episodes, followed by C. glabrata (31%) and C. parapsilosis (20%). Overall C. tropicalis, C. krusei, C. norvegensis, and C. lusitaniae caused 7% of episodes. The crude 30-day mortality rate was 37%. Advanced age (p = 0.003) and the presence of septic shock (p = 0.038) were associated with mortality. CONCLUSIONS: Candidemia continues to be associated with a high mortality. Preventative measures should be targeted against high-risk hospitalized patients, especially those in ICUs, the elderly, and those undergoing major surgery. Local surveillance of candidemia is important to optimize management.

High-throughput whole-genome sequencing to dissect the epidemiology of Acinetobacter baumannii isolates from a hospital outbreak.

Shared care of military and civilian patients has resulted in transmission of multidrug-resistant Acinetobacter baumannii (MDR-Aci) from military casualties to civilians. Current typing technologies have been useful in revealing relationships between isolates of A. baumannii but they are unable to resolve differences between closely related isolates from small-scale outbreaks, where chains of transmission are often unclear. In a recent hospital outbreak in Birmingham, six patients were colonised with MDR-Aci isolates indistinguishable using standard techniques. We used whole-genome sequencing to identify single nucleotide polymorphisms in these isolates, allowing us to discriminate between alternative epidemiological hypotheses in this setting.

Central venous catheter-related bloodstream infections: improving post-insertion catheter care.

Patients with central venous catheters (CVCs) are at increased risk of bloodstream infections and sepsis-related death. CVC-related bloodstream infections (CRBSIs) are costly and account for a significant proportion of hospital-acquired infections. The aim of this audit was to assess current practice and staff knowledge of CVC post-insertion care and therefore identify aspects of CVC care with potential for improvement. We conducted a prospective audit over 28 consecutive days at a university teaching hospital investigating current practice of CVC post-insertion care in wards with high CVC usage. A multiple choice questionnaire on best practice of CVC insertion and care was distributed among clinical staff. Rates of breaches in catheter care and CRBSIs were calculated and statistical significance assumed when P<0.05. Data was recorded from 151 CVCs in 106 patients giving a total of 721 catheter days. In all, 323 breaches in care were identified giving a failure rate of 44.8%, with significant differences between intensive care unit (ICU) and non-ICU wards (P<0.001). Dressings (not intact) and caps and taps (incorrectly placed) were identified as the major lapses in CVC care with 158 and 156 breaches per 1000 catheter days, respectively. During the study period four CRBSIs were identified, producing a CRBSI rate of 5.5 per 1000 catheter days (95% confidence interval: 0.12-10.97). There are several opportunities to improve CVC post-insertion care. Future interventions to improve reliability of care should focus on implementing best practice rather than further education.

Experience applying the UK meticillin-resistant Staphylococcus aureus (MRSA) guidelines in a tertiary referral hospital in the United Arab Emirates 1999-2002: same guidelines, different cultures.

Meticillin-resistant Staphylococcus aureus (MRSA) is an important nosocomial pathogen worldwide. There are few reports concerning MRSA in the United Arab Emirates (UAE). We report our experience with MRSA in a 400-bed tertiary referral hospital in the UAE, which followed the UK MRSA guidelines. MRSA data were reviewed to include demographic and clinical data on all new MRSA cases; a review of the ward environment including number of single rooms, sinks, toilets and bathrooms, frequency of cleaning; cultural observations; and number of infection control personnel per beds. MRSA was an uncommon pathogen. There were 90 new MRSA cases from 1999 to 2002 including two clusters of MRSA. While the procedures followed were the same as those in the UK, there were differences in the hospital environment compared with the UK and in cultural aspects of the patients' behaviour. At least 70% of inpatients were in single rooms with ensuite bathrooms. It was rare for more than two patients to share a toilet or bathroom. There were fewer than recommended infection control personnel and no antibiotic restriction policy in the hospital. Cleaners were on the wards for >100 h per week and were available 24 h per day for rapid response. We conclude that there are many factors that influence the management and control of MRSA, including cultural and social behaviour.

A survey of antimicrobial resistance in a tertiary referral hospital in the United Arab Emirates.

Published data on antimicrobial resistance are lacking for the United Arab Emirates (UAE). Knowledge of local patterns of resistance is essential to optimize guidelines for empirical antimicrobial treatment. Awareness of susceptibility patterns in other parts of the world may be important for determining empirical antimicrobial therapy for travelers or patients transferred from abroad. Antibiograms from unique isolates of common hospital and community bacteria are described in a tertiary referral hospital in the UAE, which had no antimicrobial restrictions and limited resources. Antimicrobial resistance rates were unpredictable and were high for Gram-negative organisms, such as Escherichia coli, Shigella sonnei, Campylobacter spp, and also Streptococcus pneumoniae. In contrast, methicillin-resistant Staphylococcus aureus (MRSA) comprised less than 5% of S. aureus isolates and glycopeptide-resistant enterococci (GRE) were not detected during the surveillance period. Our results provide data on antimicrobial resistance for the UAE and highlight the need for resources for surveillance of antimicrobial resistance.

Hand hygiene: simple and complex.

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

The changing pattern of bloodstream infection in pediatric oncology patients in the United Arab Emirates.

A surveillance study was performed on the pattern and antimicrobial susceptibilities of microorganisms isolated from blood cultures in the main pediatric oncology unit in the United Arab Emirates. The only previous data were published in 1995. During 1998-2000, the pattern of bloodstream infection changed. Enterobacter spp. and Enterococcus spp. emerged as frequent pathogens, while Pseudomonas aeruginosa became less common. There was a high incidence (65/198) of polymicrobial bacteremia not previously reported. This study highlights the need for continuous surveillance of the pattern of bloodstream infection in pediatric oncology patients so that changes may be detected and antimicrobial treatment modified appropriately.

Epidemiology and typing of Clostridium difficile.

Clostridium difficile is now established as the most common nosocomial enteric pathogen causing pseudomembranous colitis, antibiotic-associated colitis and antibiotic-associated diarrhoea. Antibiotic therapy is the most important risk factor in colonization and infection with C. difficile. However, other factors are involved such as age and underlying illness. The introduction of reliable typing and fingerprinting methods has demonstrated hospital acquisition and cross-infection with C. difficile and has been important in improving our understanding of the epidemiology and pathogenicity of C. difficile.