NEJM February 2026: Volume 394, Issue 7 – Medical Research & Articles

A concerning outbreak of extensively drug-resistant (XDR) Pseudomonas aeruginosa has been identified in a neonatal intensive care unit (NICU) at a hospital in Greece. The outbreak, spanning from May 2023 to December 2023, involved 18 infants, with 12 confirmed infections and six cases of colonization.

The Outbreak Unfolds

The infections occurred in premature infants with a median gestational age of 28 weeks. Researchers initiated a case-control study to determine potential risk factors. The investigation focused on identifying the source and transmission pathways of the XDR P. Aeruginosa strain.

Identifying the Culprit

Whole-genome sequencing revealed that all isolates from the affected infants were genetically indistinguishable, confirming a common source. The strain exhibited resistance to all commonly used antibiotics, including carbapenems, posing a significant challenge to treatment. The investigation pinpointed the hospital water supply as the likely source of the outbreak.

Did You Know? The outbreak spanned a period of eight months, from May 2023 to December 2023, highlighting the persistence and difficulty in controlling such infections in vulnerable populations.

Specifically, the XDR P. Aeruginosa was detected in water samples collected from the NICU, including those from the sinks and the water outlets used for preparing infant formula. Researchers found that the water system lacked adequate disinfection, creating a favorable environment for bacterial growth.

Response and Containment

In response to the outbreak, the hospital implemented several measures. These included the immediate discontinuation of water use for drinking, formula preparation and wound care within the NICU. Enhanced cleaning and disinfection protocols were also introduced. The hospital initiated a comprehensive assessment and remediation of the water system.

Expert Insight: The emergence of XDR strains in healthcare settings underscores the critical importance of robust infection control measures, particularly in vulnerable populations like premature infants. The reliance on water systems for basic care creates a potential pathway for transmission that requires vigilant monitoring, and maintenance.

What Could Happen Next

Following the interventions, the incidence of new infections and colonization cases decreased. However, continued surveillance is crucial to ensure the outbreak remains contained. Analysts expect that ongoing monitoring of the water system and adherence to strict infection control practices will be necessary to prevent recurrence.

other healthcare facilities with similar water system vulnerabilities could experience similar outbreaks. A possible next step for other hospitals may be to proactively assess their water systems and implement appropriate disinfection measures. Further research could focus on developing more effective strategies for eradicating XDR P. Aeruginosa from hospital water systems.

Frequently Asked Questions

What is XDR Pseudomonas aeruginosa?

XDR Pseudomonas aeruginosa is a strain of bacteria that is resistant to many antibiotics, including carbapenems, making it difficult to treat infections.

Where did the outbreak occur?

The outbreak occurred in the neonatal intensive care unit (NICU) of a hospital in Greece.

What was the source of the outbreak?

The source of the outbreak was identified as the hospital water supply, specifically water from sinks and outlets used for preparing infant formula.

Considering the challenges presented by antibiotic-resistant bacteria, how can healthcare facilities better protect their most vulnerable patients?