Concerns over waterborne infection risks in UK hospitals have hit the headlines over the past decade. Pseudomonas bacteria were found in the water systems of Belfast’s new state-of-the-art maternity hospital;1 21 patients were infected by bacteria in the water supply at the Royal Papworth Hospital,2 and an infection outbreak in the child cancer wards at the Queen Elizabeth University Hospital, Glasgow, is also believed to have originated from the hospital’s water systems.3
These are just some of the high-profile incidents reported in the national press — demonstrating the need for greater consultation with Infection Prevention and Control (IPC) teams, as well as further specialist training with regards to the built environment. During the conference, speakers highlighted the need for a better understanding of the risks posed by water systems and wastewater, across all stakeholders responsible for designing, building, and commissioning, hospitals. ‘Blindly following guidance’ is not enough to mitigate the risks, they warned.
During the conference, delegates heard from Dr. Michael Weinbren, a Specialist Advisor in Microbiology to the New Hospital Programme, who gave an insight into some of the outbreaks that have been found to have originated from hospital water / wastewater systems — including new builds. He pointed out that the first requirement for a hospital is that it “should do no harm”; patient safety should be “front and centre”.
Not ‘blindly following guidance’
While guidance is important, when it comes to the design, construction, and commissioning, of hospital facilities, “blindly following guidance can prove very dangerous,” he warned. He gave the example of the guidance for ‘six-monthly water testing for Pseudomonas’ — bacteria can appear between testing regimes over this period, so following this guidance could lead to a failure to identify and act rapidly on any emerging threats.
In fact, the risks of waterborne infection have been well documented, ever since the 1976 Legionnaires’ disease outbreak in Philadelphia. However, the issue has gained significant attention in the UK in the past decade, following an outbreak of Pseudomonas aeruginosa which claimed the lives of three babies at Belfast’s Royal Jubilee Maternity Hospital, in 2012.
There is now a national action plan, and in recent months we have seen the publication of the NHS Estates Technical Bulletin (NETB) No.2024/3, which looks at ‘Designing safe spaces for patients at high risk of infection from nontuberculous mycobacteria and other waterborne pathogens’ (27 August 2024).
“If you can prevent transmission in the first place, it’s much better than antimicrobial stewardship,” Dr. Weinbren commented.
The highly experienced microbiologist added that the AMR national action plan is a “step forward”, as it calls for designers, architects, engineers, and facilities managers, to work with IPC teams to deliver facilities, so that IPC needs can be anticipated. However, not everyone in infection prevention has been trained in the built environment. If people don’t know the answers, they need to be able to speak up, and we need to train people, he asserted.
Removable shower insert
He went on to highlight some of the risks posed by water outlets and wastewater, as well as a possible solution developed to address the risks associated with shower drains, with a removable and autoclavable shower insert, designed to prevent patients having direct contact with wastewater. “We need to think about the design of showers in the future,” he asserted.
Dr. Michael Weinbren went on to highlight research by Fucini et al which showed that when ITU rooms have a sink located within them (as opposed to outside), this can result in an increased rate of Pseudomonas-associated infection.4 Approximately 5% of patients, in a study by Halstead et al, ‘definitely’ acquired their P. aeruginosa from their water outlets in the intensive care unit.5
Sinks have the potential to “harm and kill patients”, Dr. Michael Weinbren warned. He also highlighted daily practices in hospitals which represent a risk — such as filling water jugs by standing them in the sink, so the jug is in contact with the wastewater drain. This can lead to infection transmission. To overcome this risk, specially designed water dispensers can be introduced that ensure there is no contact with the sink or wastewater drain.
Ultimately, he pointed out that if you cannot see the risk, you cannot mitigate it. A risk-based approach is essential. However, while we are good at recognising that patients have an infection, we are not so good at tracing this back to the water/wastewater systems.
“I think it would be fair to say that if we were able to track back every transmission event to the source, the design of the built environment would be completely different in our buildings in relation to water/wastewater,” commented Dr. Michael Weinbren.
What is down a sink?
Dr. Mark Garvey highlighted the risks of infection transmission from the environment, including hospital sinks, as part of the Tina Bradley Lecture, in a presentation titled: ‘Scoping out the IPC landscape’. Dr. Mark Garvey, a Consultant Clinical Scientist, Clinical Director of IPC, and Director of the Hospital Infection Research Laboratory, highlighted some examples of serious transmissions that have occurred – including incidents involving transmission of Hepatitis C in a renal healthcare setting,8 and waterborne Pseudomonas aeruginosa in a haematology unit.9
Transmission of infection from trays used for IV prep was identified as a serious concern in both incidents. In the haematology unit, blue IV trays were found in a sink which had no filter. This sink was proven to be a source of Pseudomonas aeruginosa, which led to three patients experiencing central line infections on the unit. Therefore, we need to think carefully about how these pieces of equipment are cleaned and decontaminated, and the risks posed by sinks, he warned.
Dr. Garvey went on to highlight the findings of further research which looked at Pseudomonas aeruginosa infection in augmented care. This project examined the molecular ecology and transmission dynamics in four large UK hospitals.10
Over a 16-week period, all water outlets in the augmented care units were sampled for P. aeruginosa, and clinical isolates were collected. They found that 20-30% of the water outlets tested positive for P. aeruginosa. The samples were genome sequenced, and patient isolates examined from previous months. As a result, they found that 60% of the isolates taken from patients who had experienced a P. aeruginosa infection matched the water isolates.
In another paper, ‘efforts to engineer out P. aeruginosa’ included new tap outlets and point-of-use filters, as well as holistic measures, such as a revised tap cleaning method, and appropriate disposal of patient wastewater. These engineering and holistic interventions resulted in a 50% reduction in the number of P. aeruginosa clinical patient isolates over a year.11
Dr. Mark Garvey further presented a slide titled: ‘What is down a sink?’, featuring graphic photos of biofilms and contamination, as well as positive samples cultured from sinks – including CPE.
He also presented some revealing research on the extent of the ‘sink splash zone’.6 This study involved placing paper towels on the floor around the splash zone of the sink. They ran the tap to see how far it would splash, and found that it splashed up to 2 metres in distance – demonstrating the risks of transmission to patients and contamination of medical equipment.
“When you look at what is around a sink on an ITU, you will find IV trolleys and the patient’s bed – what is down that sink and what is splashing about can easily get on the patient. Water has a major role to play in infection control,” Dr. Garvey commented.
He concluded by highlighting the paper by Hopman et al, which involved the removal of sinks from patient rooms and the introduction of ‘water-free patient care’, on an ICU, which resulted in a significant reduction in colonisation with MDR Gramnegative bacteria.7
Reducing water outlets in a new build hospital
Pat Cattini, a Past President of the IPS, and Corporate Director of Infection Prevention and Control at University Hospitals Sussex, highlighted a project underway at the Trust to reduce water outlets in the design of a new cancer centre, being built as part of the New Hospital Programme.
The new cancer centre, once completed, will centralise the Trust’s non-surgical haematology and oncology services, and the accommodation will be in single rooms with an en suite. However, the initial planned design would have meant significant exposure of this vulnerable patient group to water outlets (4-5 outlets if following the Health Building Note [HBN] — which includes a clinical handwash basin, toilet, shower, and patient washbasin).
Pat Cattini pointed to a growing body of research that highlights the potential infection risks associated with exposure to water outlets, including research by Mark Garvey et al, which was presented earlier in the conference.6 This study looked at the ‘splash zone’ around water outlets, highlighting the potential infection risks (particularly from Pseudomonas aeruginosa) associated with water outlets on an ICU.
Joost Hopman et al’s study also reported a reduced rate of intensive care unit-acquired gram-negative bacilli after the removal of sinks and the introduction of ‘water-free’ patient care.7 Pat Cattini also highlighted the retrospective analysis of 552 ICUs, by Fucini et al, which found that sinks in patient rooms in ICUs are associated with higher rates of hospital-acquired infection.4
“I was concerned about the vulnerable cancer patients that will be going into our new unit,” commented Pat Cattini. “The New Hospital Programme is asking for 100% single rooms, and that means that there’s going to be a lot of water outlets to clean, flush, and maintain. Of course we need our water outlets; we need to provide water for hand hygiene and for personal hygiene — particularly mouth care, which we’ve been hearing so much about during this conference.
“The evidence is that water is still the best thing to deal with norovirus and C. difficile. So, we don’t want staff to not have access to water — although I would argue that, for many things, alcohol hand rubs are the gold standard. However, we do need to start thinking differently.
“What about the products of the future?… We know that there are at least two companies now producing hypochlorous acid products, which can be used as a hand disinfectant, which they claim to be effective against C. difficile and norovirus.
“So, it may be that we have an alternative to handwashing basins for clinical staff. We need to understand and balance our risks, and we need to think very carefully,” Pat Cattini commented.
In another new building, recently opened at the Trust, it was found that there were excess handwash basins — resulting in some not being used on a regular basis. This may increase the potential risks associated with waterborne infection and ‘dead legs’.
Hence, the IPC team proposed a derogation for the next build which would reduce the number of outlets. This included removing the handwash basin from the patient bed space (in response to the Fucini paper),4 and from the clean utility room.
Concern over sink availability
The Estates team flagged this as a ‘derogation’ from the HBN, and was concerned about proceeding without authorisation. There was also a concern that staff would be unhappy with no sink in the bedroom, and anxiety around the fact that there was no sink availability in the drug room to cope with a chemotherapy spill. The request was presented and approved by the Trust’s executive team, and endorsed by the New Hospital Programme.
Risk assessments were undertaken to ensure the appropriate mitigations were in place, and additional training provided for staff on water hygiene, so that they fully understand the reasons for caution with water outlets. The Trust is also planning a trial of a novel product based on hypochlorous acid hand sanitiser, which could have the potential to reduce the need for water outlets in the future.
“We asked to take out the clinical handwash basin in the patient’s bedroom, leaving a sink that could be used for hand washing of soiled hands in the patient’s bathroom. That would be the patient’s sink that they wash, shave, and brush their teeth in,” Pat Cattini explained.
“We also asked for no handwash basin in the clean utility/drug preparation rooms. You shouldn’t have wash basins in a pharmacy setting where you are preparing drugs. Too often we see a counter where nurses are expected to prepare IV medication — often the space is very tight and cluttered, and there’s a handwash basin nearby.
“We also suggested that we put no handwash basins in the clinical consulting room, as in those settings, alcohol rub is sufficient.”
She further highlighted concerns over water coolers and fountains within haematology and cancer settings. The potential benefits of the project include:
- Reduced patient infection risk from water outlets and drain splashes.
- Reducing the cost of treating patient infection — extra bed days, extra antibiotics, and lower mortality.
- Reduced installation costs of unnecessary sinks.
- Reduced ongoing maintenance cost for cleaning (about £1,000 per year).
- Reducing the additional cost of six-monthly water sampling in augmented care.
- Reducing the cost of filters where outlets are positive (£30-45 each).
The IPC team linked in with the New Hospital Programme expert, Dr. Michael Weinbren, for advice and support. They presented an options appraisal which was accepted by the Trust prior to meeting with representatives from the NHP for their sign off. Risk assessment documents were produced to ensure appropriate mitigations were in place.
“Innovation towards patient safety”
Ultimately, the team from the New Hospital Programme considered that the reduction of water outlets was an “innovation towards patient safety”, rather than a derogation, and perceived that it was a good opportunity to veer away from outdated guidance to improve patient safety.
The new technical bulletin, released in August 2024, endorses this risk-based approach for water hygiene, and states: “Wash-hand basins and clinical sinks should not be fitted in high-risk patient rooms where the risk assessment indicates there is too high a risk of infection from outlets and associated drainage.”
It adds that: “It is important that all parties involved understand that buildings that are compliant are not necessarily safe.”
In conclusion, Pat Cattini commented that ‘it may seem an anathema for an infection control nurse to advocate the removal of washing basins’. “However,” she said, “we need to carefully think about how we use them going forward.”
- This article, titled ‘Should we have less sinks in hospitals?’, first appeared in the March 2025 edition of The Clinical Services Journal. HEJ acknowledges the help of its author – CSJ’s editor, Louise Frampton, and the Infection Prevention Society, in allowing its re-publication here
The Infection Prevention Society
The Infection Prevention Society (IPS) is a charity with 2,000 members, all working together to prevent infections that can be avoided. Its goal is to create a world where no one is harmed by a preventable infection.
It works with healthcare professionals, policymakers, and the public, to share knowledge, support good practices, and improve infection prevention in healthcare. This helps make care safer for patients, their families, and healthcare workers.
IPS’s next annual conference, Infection Prevention 2025, will be held in Brighton on 29– 30 September. To find out more, visit https:// ip2025conference.co.uk/
References
1 Pseudomonas bacteria found in 459 water outlets of new maternity unit — Dodds. 26 November 2024. https://www.thenational.scot/news/national/24751698.pseudomonas-bacteria-found-459-water-outlets-new-maternity-unit—dodds/
2 21 patients infected by bacteria in the water supply at Royal Papworth Hospital, 7 September 2020. https://www.cambridge-news.co.uk/news/local-news/21-patients-infected-bacteria-water-18893946
3 Water at two Glasgow hospitals had ‘widespread contamination’, BBC News, 22 February 2019. https://www.bbc.co.uk/news/uk-scotland-glasgow-west-47336555
4 Fucini GB, Geffers C, Schwab F, Behnke M, Sunder W, Moellmann J, Gastmeier P. Sinks in patient rooms in ICUs are associated with higher rates of hospital-acquired infection: a retrospective analysis of 552 ICUs. J Hosp Infect. 2023 Sep;139:99-105. doi: 10.1016/j.jhin.2023.05.018. Epub 2023 Jun 10. PMID: 37308060.
5 Halstead FD, Quick J, Niebel M, Garvey M, Cumley N, Smith R, Neal T, Roberts P, Hardy K, Shabir S, Walker JT, Hawkey P, Loman NJ. Pseudomonas aeruginosa infection in augmented care: the molecular ecology and transmission dynamics in four large UK hospitals. J Hosp Infect. 2021 May;111:162-168. doi: 10.1016/j.jhin.2021.01.020. Epub 2021 Feb 1. PMID: 33539934.
6 Garvey MI, Williams N, Gardiner A, Ruston C, Wilkinson MAC, Kiernan M, Walker JT, Holden E. The sink splash zone. J Hosp Infect. 2023 May;135:154-156. doi: 10.1016/j.jhin.2023.01.020. Epub 2023 Mar 3. PMID: 36870392.
7 Hopman J, Tostmann A, Wertheim H, Bos M, Kolwijck E, Akkermans R, Sturm P, Voss A, Pickkers P, Vd Hoeven H. Reduced rate of intensive care unit acquired gram-negative bacilli after removal of sinks and introduction of ‘water-free’ patient care. Antimicrob Resist Infect Control. 2017 Jun 10;6:59. doi: 10.1186/s13756-017-0213-0. PMID: 28616203; PMCID: PMC5466749.
8 Garvey MI, Bradley CW, Holden KL, Hewins P, Ngui SL, Tedder R, Jumaa P, Smit E. Use of genome sequencing to identify hepatitis C virus transmission in a renal healthcare setting. J Hosp Infect. 2017 Jun;96(2):157-162. doi: 10.1016/ j.jhin.2017.01.002. Epub 2017 Jan 16. PMID: 28196726.
9 Garvey MI, Bradley CW, Holden E. Waterborne Pseudomonas aeruginosa transmission in a hematology unit? Am J Infect Control. 2018 Apr;46(4):383-386. doi: 10.1016/ j.ajic.2017.10.013. Epub 2017 Nov 28. PMID: 29195780.
10 Halstead FD, Quick J, Niebel M, Garvey M, Cumley N, Smith R, Neal T, Roberts P, Hardy K, Shabir S, Walker JT, Hawkey P, Loman NJ. Pseudomonas aeruginosa infection in augmented care: the molecular ecology and transmission dynamics in four large UK hospitals. J Hosp Infect. 2021 May;111:162-168. doi: 10.1016/j.jhin.2021.01.020. Epub 2021 Feb 1. PMID: 33539934.
11 Garvey MI, Bradley CW, Wilkinson MAC, Bradley C, Holden E. Engineering waterborne Pseudomonas aeruginosa out of a critical care unit. Int J Hyg Environ Health. 2017 Aug;220(6):1014-1019. doi: 10.1016/j.ijheh.2017.05.011. Epub 2017 May 31. PMID: 28592358.
Acknowledgement
n This article, titled ‘Should we have less sinks in hospitals?’, first appeared in the March 2025 edition of The Clinical Services Journal. HEJ acknowledges the help of its author — CSJ’s editor, Louise Frampton, and the Infection Prevention Society, in allowing its re-publication here.