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 2000-2022. 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 multimodal 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.

Implementing changes to reduce infections in ICU patients. Water services and waste systems

Background

Evidence linking the role of water services in transmission of infection to patients in ICUs has increased in recent years.

Aims

This research based commentary set out to identify potential solutions for water and wastewater systems in ICU settings.

Methods

Databases and open source information was used to obtain data on approaches to water and wastewater-related issues in ICU settings. This and the authors experiences have been used to describe approaches to these problems.

Findings

The lack of updated guidance has required some ICUs to develop unique responses, including 'water free' patient care combined with reduction in water services. The options consider guidance, compliance, training and education as key factors to successful outcomes and protecting vulnerable patients in ICU.

Discussion

The authors found a number of problems with water and wastewater systems in ICU to which there has not been a cohesive response in terms of guidance to support users and designers. The resultant void permits new projects to proceed with suboptimal and designs which place patients and staff at risk. As an interim measure a series of solutions suitable for existing units and new builds need to be considered.

Aspects and problems associated with the water services to be considered in intensive care units

Background

Water is a product taken for granted and assumed to be a safe commodity in intensive care units (ICU). Biofilm readily becomes established in complex water services presenting a risk to vulnerable patients. Harboured within biofilms are opportunistic pathogens which can be transmitted via hand contact, splashing, aerosol and indirect contact through medical equipment. Evidence linking the role of water services in transmission of infection to patients in ICUs has increased in recent years.

Aims

This research based commentary set out to identify current problems with water and wastewater systems in ICU settings.

Methods

Databases and open source information was used to obtain data on current water and wastewater-related issues in ICU settings. This and the authors experiences have been used to describe current challenges.

Findings

the authors found a number of problems with water systems in ICU to which there has not been a cohesive response in terms of guidance to support users and designers. The resultant void permits new projects to proceed with suboptimal and designs which place patients and staff at risk.

Discussion

Hand hygiene stations are frequently misused or close enough to patients such that splashing poses a transmission risk. The wastewater system (drain) also presents a risk, from where Gram-negative antibiotic resistant organisms may be dispersed resulting in untreatable patient infections. The water and wastewater system provide a superhighway for the movement of pathogenic microorganisms and these risks need to be addressed if we are to safeguard vulnerable users in ICU.

Factors to consider in the safe design of intensive care units - Part 1: historical aspects and ventilation systems

Background

Evidence linking the role of ventilation systems in transmission of infection to patients in intensive care units has increased in recent years.

Aims

This research-based commentary set out to identify the historical aspect of intensive care unit design, current problems and some potential solutions with respect to ventilation systems.

Methods

Databases and open source information was used to obtain data on the historical aspects and current guidance in ICU, and the authors experiences have been used to suggest potential solutions to ventilation problems in ICU.

Findings

The authors found a number of problems with ventilation in ICU to which there has not been a cohesive response in terms of guidance to support users and designers. The resultant void permits new projects to proceed with suboptimal and designs which place patients and staff at risk.

Discussion

The NHS is now at the start of major new investments in healthcare facilities in England and this together with the end of the antibiotic era mandates new guidance to address these major concerns.

Cupriavidus spp and other waterborne organisms in healthcare water systems across the United Kingdom

BACKGROUND

Cupriavidus pauculus is a rare clinical pathogen with cases having 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

The aim of this study was 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. We 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, we tested water samples for the presence of other Gram negative waterborne organisms.

METHODS

Water samples were received from ten UK NHS hospitals and from various parts of the water system. Isolates were plated on to TSA and Pseudomonas Isolation Agar and further identified using MALDI-TOF and 16S PCR FINDINGS: Cupriavidus spp. were detected in four of ten hospitals tested and all five isolates were from the periphery of the water system. All hospitals had evidence of other OPPPs. Cupriavidus spp. were identified using TSA, with some isolates growing on Pseudomonas isolation agar; as such they may be inadvertently be detected when testing water specifically for Pseudomonas aeruginosa.

CONCLUSION

This study demonstrates that isolation of Cupriavidus spp. was not unique to the Glasgow incident, these bacteria being present in hospital water systems elsewhere in the UK. We therefore recommend water testing in response to clinical cases. Consideration should also be given to water testing following bacteraemias due to other rare and unusual water borne pathogens.

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.

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.

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.

An unusual transmission event of Neisseria meningitidis serogroup W135 type 2a in a healthcare setting, England, 2012

We report an outbreak of Neisseria meningitidis serogroup W135, associated with a transient transmission event between asymptomatic individuals in a healthcare setting. Two elderly persons subsequently developed invasive meningococcal disease. The duration and type of close contact for those directly involved in the probable transmission incident would not have warranted chemoprophylaxis according to current guidelines. Meningococcal infection in older persons usually presents with pneumonia rather than meningitis or septicaemia with purpura.

A modified ATP benchmark for evaluating the cleaning of some hospital environmental surfaces

Hospital cleaning continues to attract patient, media and political attention. In the UK it is still primarily assessed via visual inspection, which can be misleading. Calls have therefore been made for a more objective approach to assessing surface cleanliness. To improve the management of hospital cleaning the use of adenosine triphosphate (ATP) in combination with microbiological analysis has been proposed, with a general ATP benchmark value of 500 relative light units (RLU) for one combination of test and equipment. In this study, the same test combination was used to assess cleaning effectiveness in a 1300-bed teaching hospital after routine and modified cleaning protocols. Based upon the ATP results a revised stricter pass/fail benchmark of 250 RLU is proposed for the range of surfaces used in this study. This was routinely achieved using modified best practice cleaning procedures which also gave reduced surface counts with, for example, aerobic colony counts reduced from >100 to <2.5 cfu/cm(2), and counts of Staphylococcus aureus reduced from up to 2.5 to <1 cfu/cm(2) (95% of the time). Benchmarking is linked to incremental quality improvements and both the original suggestion of 500 RLU and the revised figure of 250 RLU can be used by hospitals as part of this process. They can also be used in the assessment of novel cleaning methods, such as steam cleaning and microfibre cloths, which have potential use in the National Health Service.

Surveillance of respiratory virus infections in adult hospital admissions using rapid methods

Both influenza and respiratory syncytial virus (RSV) cause epidemics of respiratory illness of variable severity during the winter season. Influenza in particular has been blamed for hospital winter bed pressures, although it is thought that RSV may also play a role. Human metapneumovirus (hMPV) is a new respiratory virus reported to be important in children; only a limited number of studies are available for adult populations. We aimed to determine initially the burden of virologically confirmed infections, i.e. influenza, RSV and hMPV using polymerase chain reaction (PCR) technology and, in addition, to assess the feasibility of this approach as a surveillance tool for these respiratory viruses. Adult patients admitted to hospital in the previous 24 hours with onset of acute respiratory symptoms in the last 14 days were asked to participate. Informed written consent was obtained and nose and throat swabs taken. Multiplex PCR for influenza A (H1N1 and H3N2), influenza B and RSV A and B were carried out together with a separate PCR for hMPV. A total of 219 patients in 2001-2002 and 216 in 2002-2003 were tested and the combined results for both seasons were: 8 positive for influenza A/H1N1, 14 for influenza A/H3N2, 2 for influenza B, 14 for RSV A and 6 for RSV B. Most patients (261/435) were >65 years and most positives (30/44) were found within this age group. A number of patients aged >65 years who were positive for influenza (12/15) reported having had vaccine. In total, 373 samples were tested for hMPV and 20 were found positive across all age groups except the 45-54 years age group. As influenza activity was low during the study period the impact of infection on admissions could not be assessed. Nevertheless the viruses studied accounted for 15% of hospital admissions for respiratory infection. Most patients were aged >65 years, as expected. In the two years studied RSV and hMPV were each responsible for as many hospitalized cases of respiratory infection as influenza. Influenza infection must be considered even in those who give a history of vaccination. The molecular methods used in this study showed that surveillance of these respiratory viruses can be conducted and may help in the management of patients.

Brain catecholamines: relation to defense reaction evoked by acute brainstem transection in cat

The concentration of noradrenaline, but not serotonin, in the brainstem of cats is reduced 3 hours after the production of a defense reaction by supracollicular decerebration, even when movements and changes in blood pressure are abolished by transection of the spinal cord. After midcollicular decerebration, which does not elicit a defense reaction, noradrenaline concentrations do not change. The decrease in its concentration accompanying the defense reaction produtced by brain lesions probably reflects activity, in this behavior, of neturons containinig noradrenaline.

Generalized Infection of Muscles with Cysticercus cellulosæ; measurements of cysts and comparison with those of Trichinella spiralis

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Surgical and Pulmonary Tuberculosis

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