Waterborne infections in haemato-oncology units - a narrative review.

Bone marrow transplant and haemato-oncology patients are at risk of healthcare-associated infections due to waterborne pathogens. We undertook a narrative review of waterborne outbreaks in haemato-oncology patients from 2000 to 2022. Databases searched included PubMed, DARE and CDSR, and were undertaken by two authors. We analysed the organisms implicated, sources identified and infection prevention and control strategies implemented. The most commonly implicated pathogens were Pseudomonas aeruginosa, non-tuberculous mycobacteria and Legionella pneumophila. Bloodstream infection was the most common clinical presentation. The majority of incidents employed multi-modal strategies to achieve control, addressing both the water source and routes of transmission. This review highlights the risk to haemato-oncology patients from waterborne pathogens and discusses future preventative strategies and the requirement for new UK guidance for haemato-oncology units.

Cupriavidus spp. and other waterborne organisms in healthcare water systems across the UK.

BACKGROUND: Cupriavidus pauculus is a rare clinical pathogen, cases of which have been linked to contaminated hospital water systems. An outbreak of three cases of C. pauculus and other waterborne organisms was reported in a Glasgow hospital in 2018. AIMS: To determine whether Cupriavidus spp. are present in hospital water systems elsewhere in Scotland and the UK, and to ascertain the optimal laboratory methodology for detection. This study also sought to establish where in the water system these organisms are detected, and whether a selective media could be developed for isolation. In addition, water samples were tested for the presence of other Gram-negative waterborne organisms. METHODS: Water samples were received from 10 UK National Health Service hospitals and from various parts of the water system. Isolates were plated on to tryptone soya agar (TSA) and Pseudomonas isolation agar, and were further identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry and 16S polymerase chain reaction. FINDINGS: Cupriavidus spp. were detected in four of 10 hospitals tested, and all five isolates were from the periphery of the water system. All hospitals had evidence of other opportunistic premise plumbing pathogens. Cupriavidus spp. were identified using TSA, with some isolates growing on Pseudomonas isolation agar; as such, they may be detected inadvertently when testing water specifically for Pseudomonas aeruginosa. CONCLUSION: Isolation of Cupriavidus spp. was not unique to the Glasgow incident, and these bacteria are present in hospital water systems elsewhere in the UK. Water testing in response to clinical cases is recommended. Consideration should also be given to water testing following bacteraemias due to other rare and unusual water-borne pathogens.

Water springing to life the fungal desert.

Immunosuppressed patients are at increased risk of developing hospital-acquired fungal infections. The risk of fungal infection from construction is well established, but water ingress also presents a risk if it is not dealt with promptly. This article describes four such scenarios and the learning points from each. Water ingress may go under-reported and, as such, may be an underestimated source of fungal healthcare-associated infections.

Drains and the periphery of the water system - what do you do when the guidance is outdated?

The periphery of the water system (defined as the last 2 m of pipework from an outlet and ensuing devices including drainage), is the juncture of multiple inherent risks: the necessity to use materials with higher risk of biofilm formation, difficulty in maintaining safe water temperatures, a human interface with drainage systems, poor design, poor layout and use by staff. Add to this risk a large new healthcare facility capital build programme in England, outdated guidance and bacteria emanating from drainage systems containing highly mobile genetic elements (threatening the end of the antibiotic era), and the scene is set for the perfect storm. There is an urgent need for the re-evaluation of the periphery of the water system and drainage systems. Consequently, in this article we examine the requirement and placement of hand wash stations (HWSs), design of showers, kitchens and the dirty utility with respect to water services. Lastly, we discuss the provision of safe water to high-risk patient groups. The purpose of this article is to stimulate debate and provide infection control and design teams with support in deviating from the outdated existing guidance and to challenge conventional thinking until new advice is forthcoming.

Dissemination of antibiotic resistance and other healthcare waterborne pathogens. The price of poor design, construction, usage and maintenance of modern water/sanitation services.

Classical waterborne pathogens (cholera/typhoid) drove the development of safe water and sanitation during the industrial revolution. Whilst effective against these organisms, other bacteria exploited the potential to form biofilm in the narrow pipes of buildings. 1976 saw the discovery of legionella. Despite evidence dating back to 1967 (including paediatric deaths in Manchester in 1995 from splashes from a sink contaminating parenteral nutrition) it required the deaths of four neonates and the might of the Press in 2011 for the UK medical services to accept waterborne transmission of other Opportunistic Plumbing Premise Pathogens (OPPP). Human nature, a healthcare construction industry largely devoid of interest in water safety, and failures in recognising transmission are major forces hindering progress in preventing infection/deaths from waterborne infections. The advent of highly resistant Gram-negative bacteria is highlighting further deficiencies in modern drainage systems. These bacteria are not thought to have special adaptations promoting their dispersal but purely attract our attention to the well-trodden routes used by sensitive organisms, which go undetected. The O'Neill report warns of the bleak future without effective antibiotics. This paper examines the evidence as to why modern water services/sanitation continue to present a risk to patient safety (and the general public) and also suggests their designs may be flawed if they are to stem the modern equivalent of cholera, the dissemination of antibiotic resistance.

Observation study of water outlet design from a cross-infection/user perspective: time for a radical re-think?

BACKGROUND: Handwashing is a key barrier to cross-infection performed at a handwash station (HWS). Elbow-operated outlets, if used incorrectly (with hands), become highly touched objects, potentially providing a route for cross-infection. AIM: To study how elbow-operated outlets were used by staff in this hospital, whether the correct type of HWS had been installed in the various ward areas according to the Health Building Note (HBN) 00-10 Part C: Sanitary Assemblies (hands-free outlets in clinical, food preparation and laboratory areas), and factors impinging on design/setup which may affect compliance with correct use. METHODS: Observation of outlet use was performed by mounting a video camera above four HWSs. Review of suitability of outlet was conducted by two of the authors by visiting ward areas and assessing compliance against HBN recommendations. Angle of elbow-operated lever setup was measured using a protractor and water temperature in relation to angle of movement of elbow lever was measured using a calibrated thermocouple. FINDINGS: Ninety-two percent of staff used hands to turn on the outlet and 68% used hands to turn the outlet off, potentially re-contaminating their hands. More than 70% of users moved the lever ≤45°. Almost half of elbow levers were set up incorrectly, being flush or within 3.5 cm of the rear panel, making elbow operation extremely difficult. Selection of outlet type according to HBN was most incorrect in the intensive treatment unit but also occurred in the newly built parts of the hospital. CONCLUSIONS: Although handwashing is a key barrier to cross-infection, poor selection and incorrect use of outlet undermines its effectiveness. Design and incorrect instalment further compromise the intended means of operation of elbow levers. Of equal concern is that this risk mostly goes unrecognized. There is an opportunity to improve handwashing safety, but it requires engagement across a broad stratum from Government Departments of Health and manufacturers down to the user.

The handwash station: friend or fiend?

Handwashing is a key barrier to cross-infection performed at a handwash station (HWS, an interface between water and drainage systems). Widespread and often uncritical placement/design and use of HWSs is not without attendant risks. Recognition of the associated hazards went unheeded for over 45 years despite warnings in the literature, until the neonatal outbreak of pseudomonas in Belfast in 2012 forced change. Minimizing risk requires a holistic approach beyond the mere testing of water from the outlet of a HWS for the presence of Pseudomonas aeruginosa or other pathogens. Literature reports of outbreaks linked to HWSs outside of neonatal units are over-represented by multi-resistant organisms, and increasingly by carbapenemase-producing organisms. Evidence suggests that a large proportion of waterborne transmissions go undetected. Much could be done to improve current design, use and placement of HWSs, and this is assessed critically in this article.

Optimization of the blood culture pathway: a template for improved sepsis management and diagnostic antimicrobial stewardship.

Laboratory processing of blood cultures has remained static over the past 30 years, despite increasing antibiotic resistance and advances in analyser design. At the study hospital, siting the blood culture analyser in the blood sciences laboratory and optimizing the pre-analytical and analytic phases of blood culture management resulted in a reduction in the time taken to detect most blood culture isolates to <12h. Fifty percent of positive blood cultures containing Escherichia coli were definitively reported with antibiotic susceptibilities in <24h. More than 85% of blood cultures positive for E. coli had antibiotic susceptibilities reported within 36h of collection, compared with 66h at a comparator hospital.

Giving the tap the elbow? An observational study.

BACKGROUND: Handwashing is viewed as the most important barrier to cross-infection. Incorrect use of clinical handwash basins may lead to cross-infection either from contaminated water or due to failure to decontaminate hands. Elbow-operated taps used correctly prevent recontamination of hands during operation. Many elbow-operated taps are installed incorrectly, with the handle flush with the back panel, making it difficult to open using the elbow. AIM: To determine the effect of altering the angle of the handle of elbow-operated taps on handwashing technique. METHODS: An observational study was conducted using two rooms; in one the handles of the elbow-operated taps were flush with the inspection panel behind, and in the other they were set at 35°. FINDINGS: Thirty-five staff members washed their hands in both rooms. Hands were used to turn on the taps in 97% of instances. In 57% of washes hands were recontaminated when used to turn the tap off. Only six individuals consistently used their elbows to turn outlets off. Surprisingly, more individuals used their elbows to operate taps whose handles were flush with the inspection panel behind. CONCLUSION: Greater emphasis needs to be placed on correct use of elbow-operated outlets. The decision to use elbow- or sensor-operated outlets is not clear-cut, as each has pros and cons. There is much room for improvement in design and standardization of handwash basins. Given the importance of handwashing it is surprising that these gaps exist.