Peter Hoffman

Insidious risk of severe mycobacterium chimaera infection in cardiac surgery patients

Background. An urgent UK investigation was launched to assess risk of invasive Mycobacterium chimaera infection in cardiothoracic surgery and a possible association with cardiopulmonary bypass heater-cooler units following alerts in Switzerland and The Netherlands. Methods. Parallel investigations were pursued: (1) identification of cardiopulmonary bypass–associated M. chimaera infection through national laboratory and hospital admissions data linkage; (2) cohort study to assess patient risk; (3) microbiological and aerobiological investigations of heater-coolers in situ and under controlled laboratory conditions; and (4) whole-genome sequencing of clinical and environmental isolates. Results. Eighteen probable cases of cardiopulmonary bypass–associated M. chimaera infection were identified; all except one occurred in adults. Patients had undergone valve replacement in 11 hospitals between 2007 and 2015, a median of 19 months prior to onset (range, 3 months to 5 years). Risk to patients increased after 2010 from <0.2 to 1.65 per 10000 person-years in 2013, a 9-fold rise for infections within 2 years of surgery (rate ratio, 9.08 [95% CI, 1.81–87.76]). Endocarditis was the most common presentation (n = 11). To date, 9 patients have died. Investigations identified aerosol release through breaches in heater-cooler tanks. Mycobacterium chimaera and other pathogens were recovered from water and air samples. Phylogenetic analysis found close clustering of strains from probable cases. Conclusions. We identified low but escalating risk of severe M. chimaera infection associated with heater-coolers with cases in a quarter of cardiothoracic centers. Our investigations strengthen etiological evidence for the role of heater-coolers in transmission and raise the possibility of an ongoing, international point-source outbreak. Active management of heater-coolers and heightened clinical awareness are imperative given the consequences of infection.

Evaluation of the sporicidal activity of different chemical disinfectants used in hospitals against Clostridium difficile

Decontamination of surfaces and medical equipment is integral to the control of Clostridium difficile transmission, and many products claim to inactivate this bacterium effectively. Thirty-two disinfectants were tested against spores of C. difficile in a suspension test based on European Standard BS EN 13704:2002, with contact times of 1 and 60 min in simulations of clean (0.3% albumin) and dirty (3% albumin) conditions. The addition of a 1-min contact time was chosen as a more realistic simulation of probable real-life exposures in the situation being modelled than the 60 min specified by the Standard. The manufacturers lowest recommended concentrations for use were tested. Sixteen products achieved >10(3) reduction in viability after 60 min (the pass criterion for the Standard) under both clean and dirty conditions. However, only eight products achieved >10(3) reduction in viability within 1 min under dirty conditions. Three products failed to reduce the viability of the C. difficile spores by a factor of 10(3) in any of the test conditions. This study highlights that the application of disinfectants claiming to be sporicidal is not, in itself, a panacea in the environmental control of C. difficile, but that carefully chosen environmental disinfectants could form part of a wider raft of control measures that include a range of selected cleaning strategies.

Decontamination of breast pump milk collection kits and related items at home and in hospital: guidance from a Joint Working Group of the Healthcare Infection Society and Infection Prevention Society.

INTRODUCTION A variety of methods are in use for decontaminating breast pump milk collection kits and related items associated with infant feeding. This paper aims to provide best practice guidance for decontamination of this equipment at home and in hospital. It has been compiled by a Joint Working Group of the Healthcare Infection Society and the Infection Prevention Society. METHODS The guidance has been informed by a search of the literature in Medline, the British Nursing Index, the Cumulative Index to Nursing and Allied Health Literature, Midwifery and Infant Care, and the results of two surveys of UK neonatal units in 2002/3 and 2006, and of members of the Infection Prevention Society in 2014. Since limited good quality evidence was available from these sources, much of the guidance represents good practice based on the consensus view of the Working Group. KEY RECOMMENDATIONS CONCLUSION This guidance provides practical recommendations to support the safe decontamination of breast pump milk collection kits for healthcare professionals to use and communicate to other groups such as parents and carers.

The hospital microbiome project: meeting report for the UK science and innovation network UK-USA workshop ‘beating the superbugs: hospital microbiome studies for tackling antimicrobial resistance’, October 14th 2013

The UK Science and Innovation Network UK-USA workshop ‘Beating the Superbugs: Hospital Microbiome Studies for tackling Antimicrobial Resistance’ was held on October 14th 2013 at the UK Department of Health, London. The workshop was designed to promote US-UK collaboration on hospital microbiome studies to add a new facet to our collective understanding of antimicrobial resistance. The assembled researchers debated the importance of the hospital microbial community in transmission of disease and as a reservoir for antimicrobial resistance genes, and discussed methodologies, hypotheses, and priorities. A number of complementary approaches were explored, although the importance of the built environment microbiome in disease transmission was not universally accepted. Current whole genome epidemiological methods are being pioneered in the UK and the benefits of moving to community analysis are not necessarily obvious to the pioneers; however, rapid progress in other areas of microbiology suggest to some researchers that hospital microbiome studies will be exceptionally fruitful even in the short term. Collaborative studies will recombine different strengths to tackle the international problems of antimicrobial resistance and hospital and healthcare associated infections.

Multiuse patient monitoring equipment as a risk factor for acquisition of Candida auris

Introduction: Candida auris is an emerging and multi-drug resistant pathogen recently associated with outbreaks worldwide, often in intensive care settings. We describe our experience of patient and environmental screening during an outbreak in the Neurological Intensive Care Unit (NITU) of a large teaching hospital Trust. Methods: Patients were screened on admission to the NITU, weekly and on discharge from October 2016 to May 2017. Various methodologies for environmental screening were used with an emphasis on sampling high-touch areas and multi-use devices. Results: Between the end of October 2016 to the end of May 2017 fifty-eight patients became C. auris colonised or infected, including two cases of candidaemia. Fifty-seven of the 58 patients colonised or infected with C. auris had been admitted to NITU during their hospital stay. C. auris detection in the NITU ward environment was low. However, the organism was detected from multiuse patient monitoring equipment (skin surface temperature probes and a pulse oximeter) and a patient hoist. Following the initial finding of C. auris on a skin surface temperature probe, C. auris was cultured from four further temperature probes. Discussion: We provide evidence that C. auris can be recovered from ‘cleaned’ skin surface temperature probes supporting the hypothesis that re-usable equipment is a risk factor for colonisation/infection with this organism. The use of skin surface temperature probes has been discontinued on the unit. Removal of the temperature probes appears to reduce the acquisition rate. Our initial observations will be further investigated by conducting a cohort study examining risk factors for colonisation and infection.

Guidance for the decontamination of intracavity medical devices: the report of a working group of the Healthcare Infection Society

BACKGROUND Intracavity medical devices (ICMDs) are used in a wide variety of healthcare settings. The approach to their decontamination and the resources available also differ widely. Their potential for infection transmission is considerable. AIM To produce a comprehensive risk assessment-based approach to the decontamination of ICMDs, accompanied by an adaptable audit tool. KEY RECOMMENDATIONS

Decontamination of breast pump milk collection kits and related items at home and in hospital: guidance from a Joint Working Group of the Healthcare Infection Society & Infection Prevention Society*:

Introduction: A variety of methods are in use for decontaminating breast pump milk collection kits and related items associated with infant feeding. This paper aims to provide best practice guidance for decontamination of this equipment at home and in hospital. It has been compiled by a joint Working Group of the Healthcare Infection Society and the Infection Prevention Society. Methods: The guidance has been informed by a search of the literature in Medline, the British Nursing Index, the Cumulative Index to Nursing & Allied Health Literature, Midwifery & Infant Care and the results of two surveys of UK neonatal units in 2002/3 and 2006, and of members of the Infection Prevention Society in 2014. Since limited good quality evidence was available from these sources much of the guidance represents good practice based on the consensus view of the Working Group. Key recommendations: Breast pump milk collection kits should not be reused by different mothers unless they have been sterilized in a Sterile Services Department between these different users. When used by the same mother, a detergent wash followed by thorough rinsing and drying after each use gives acceptable decontamination for most circumstances, as long as it is performed correctly. Additional decontamination precautions to washing, rinsing and drying may be used if indicated by local risk assessments and on advice from the departmental clinicians and Infection Prevention and Control Teams. The microbiological quality of the rinse water is an important consideration, particularly for infants on neonatal units. If bottle brushes or breast/nipple shields are used, they should be for use by one mother only. Decontamination should be by the processes used for breast pump milk collection kits. Dummies (soothers, pacifiers or comforters) needed for non-nutritive sucking by infants on neonatal units, should be for single infant use. Manufacturers should provide these dummies ready-to-use and individually packaged. They must be discarded at least every 24 hours or immediately if soiled with anything other than the baby’s saliva. No attempt should be made to decontaminate the dummies, either before or during use. Conclusion: This guidance provides practical recommendations to support the safe decontamination of breast pump milk collection kits for healthcare professionals to use and communicate to other groups such as parents and carers.