• Water filtration in neonatology

    Water hygiene and infection prevention in neonatal intensive care units (NICUs)

    In neonatal care – particularly in Neonatal Intensive Care Units (NICUs) – the microbiological quality of water is a critical factor in patient safety. Because water is used in many patient-facing activities, consistently controlled water hygiene is an essential component of infection prevention for preterm infants, high-risk newborns, and critically ill neonates.

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    Water as an underestimated risk factor in neonatal care

    Healthcare-associated infections (HAIs) remain a persistent global challenge. In the United States alone, up to 10% of hospitalized patients are affected (Anaissie et al., 2002). Preterm infants, high-risk neonates, and critically ill newborns treated in NICUs are among the most vulnerable patient populations.

    Their increased susceptibility to infection is multifactorial. In very low birth weight (VLBW* < 1500 g) preterm infants, skin and mucosal barriers are more permeable to pathogens during the first weeks of life. Invasive interventions such as catheters, drains, and intubation further compromise natural defenses. Additionally, colonization with hospital-associated microorganisms occurs through frequent environmental exposure, particularly via hands.

    Beyond traditional transmission routes, water quality has become an increasing focus in infection prevention. Analyses by the U.S. Centers for Disease Control and Prevention (CDC) covering the years 2014–2021 indicate that water-associated microorganisms were involved in approximately one-third of investigated NICU infections and outbreak events. Even when transmission pathways were not always clearly identified, recurring issues related to water use were observed.

    Clinically relevant water-associated pathogens include Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, and other multidrug-resistant gram-negative organisms. P. aeruginosa is one of the most frequently reported pathogens in NICU outbreaks and can cause life-threatening infections in preterm and critically ill neonates.

    *Very Low Birth Weight

    Water-related sources of HAIs in NICUs

    A systematic review published in the International Journal of Hygiene and Environmental Health analyzed 25 studies on water-associated HAIs in neonates and mothers. In 24 out of 25 studies, water-related sources were identified as reservoirs or transmission pathways. The most frequently implicated sources included tap water, sinks, and faucets, followed by water baths, incubators, humidifiers, ventilators, water used for infant bathing, and handwashing with contaminated water.

    Molina-Cabrillana et al. reported a Pseudomonas aeruginosa outbreak in a Spanish NICU (2011–2012), where contaminated tap water used to warm breast milk and formula in bottle warmers was identified as a potential reservoir. After switching to sterile water, no further cases occurred. Similarly, an outbreak involving ESBL**-producing Klebsiella pneumoniae in an Italian NICU was controlled through hygiene interventions and replacement of a contaminated bottle warmer.

    Fatal infections caused by Cronobacter sakazakii in 2021/2022 in Germany (Europe) and the United States – linked to contaminated powdered infant formula – highlight the need for strict hygiene protocols in formula preparation.

    Multiple studies show that hospital water outlets and drains are frequently colonized with potentially pathogenic bacteria such as Pseudomonas aeruginosa. As a waterborne organism and biofilm former, it can persist in plumbing systems, sinks, incubators, and patient environments, and spread via splashes, aerosols, and contaminated surfaces.

    Multidrug-resistant P. aeruginosa is responsible for approximately 13–19% of healthcare-associated infections in the United States annually, depending on the surveillance system (CDC/NHSN data ranges).

    A study conducted in an Italian NICU also demonstrated an association between frequent breastfeeding and colonization of neonates with an imipenem-resistant MBL*** strain of P. aeruginosa, underscoring the importance of hygienic, water-related handling processes even in otherwise protective practices.

    Additional water-related risk areas in NICUs include:

    • Cleaning of feeding bottles and breast pump equipment
    • Reprocessing of enteral feeding tubes
    • Water-based reprocessing of medical devices (e.g., catheters, ventilator components, instruments) in washer-disinfectors

    **Extended-Spectrum Beta-Lactamase
    ***Metallo-Beta-Lactamase

    Recommended infection prevention measures

    Water-associated infections in neonatal care are preventable in many cases. Water should be consistently recognized as a relevant risk factor and managed through clear protocols, effective technical precautions, and structured water safety programs. This approach helps reduce infection rates, improve clinical outcomes, and lower healthcare costs.

    In Germany (Europe), recommendations for preventing water-associated infections in healthcare settings are primarily developed by the Commission for Hospital Hygiene and Infection Prevention (KRINKO) at the Robert Koch Institute (RKI). According to Section 23 of the German Infection Protection Act (IfSG), these guidelines form the binding professional framework for hospital hygiene and must be implemented in internal clinical standards. Additional guidance is provided by organizations such as the German Society for Pediatric Infectious Diseases (DGPI) and the Federal Environment Agency (UBA).

    In the United States, comparable guidance is provided by the CDC, including water management programs (e.g., ASHRAE Standard 188) and infection prevention guidelines for healthcare facilities.

    Reliable protection through sterile filtration

    Point-of-use water filters that can be installed directly at outlets such as faucets/taps – or integrated into supply lines of water-bearing medical devices – offer a practical and cost-effective solution. These filters reliably remove pathogenic bacteria such as Pseudomonas aeruginosa, Legionella pneumophila, non-tuberculous mycobacteria (NTM) or Mycobacterium spp., Stenotrophomonas maltophili, and Klebsiella spp. from water, significantly reducing water-associated infections in critical care settings.

    Reliable protection with our i3 Point-of-Use water filters

    The Point-of-Use water filter i3 ONE is designed for the filtration of tap water at the water tap/faucet. It can be installed quickly and securely using a quick-connect system and is ideal for manual pre-cleaning of medical devices, hand hygiene, and warming of milk bottles. Its 10-degree angled design directs the water stream to minimize direct contact with the drain, reducing the formation of potentially infectious aerosols.

    The inline water filter i3 FOUR provides reliable protection against pathogenic waterborne bacteria and is installed directly into water supply systems using quick-connect couplings. Its microfiltration membrane meets stringent water hygiene requirements and supports a flow rate of 6 L/min. It is particularly suitable for automated reprocessing of medical devices in washer-disinfectors.

    The inline water filter i3 FIVE is also installed in water supply lines of medical equipment to prevent contamination by pathogenic bacteria. Despite its compact design, it supports a high flow rate of 20 L/min and is equally suitable for automated reprocessing applications.

    Our water filters act as immediately effective barriers against pathogenic bacteria, are easy to install, and support compliance with hygiene requirements – enhancing safety for both patients and healthcare professionals in daily clinical practice.





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