Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Aug 19;25(1):301.
doi: 10.1186/s13054-021-03726-y.

Outbreak of Pseudomonas aeruginosa producing VIM carbapenemase in an intensive care unit and its termination by implementation of waterless patient care

Gaud Catho  1 , R Martischang  2 , F Boroli  3 , M N Chraïti  2 , Y Martin  2 , Z Koyluk Tomsuk  3 , G Renzi  4 , J Schrenzel  4 , J Pugin  3 , P Nordmann  5   6 , D S Blanc  6   7 , S Harbarth  2
Affiliations

Outbreak of Pseudomonas aeruginosa producing VIM carbapenemase in an intensive care unit and its termination by implementation of waterless patient care

Gaud Catho et al. Crit Care. .

Abstract

Background: Long-term outbreaks of multidrug-resistant Gram-negative bacilli related to hospital-building water systems have been described. However, successful mitigation strategies have rarely been reported. In particular, environmental disinfection or replacement of contaminated equipment usually failed to eradicate environmental sources of Pseudomonas aeruginosa.

Methods: We report the investigation and termination of an outbreak of P. aeruginosa producing VIM carbapenemase (PA-VIM) in the adult intensive care unit (ICU) of a Swiss tertiary care hospital with active case finding, environmental sampling and whole genome sequencing (WGS) of patient and environmental strains. We also describe the implemented control strategies and their effectiveness on eradication of the environmental reservoir.

Results: Between April 2018 and September 2020, 21 patients became either infected or colonized with a PA-VIM strain. For 16 of them, an acquisition in the ICU was suspected. Among 131 environmental samples collected in the ICU, 13 grew PA-VIM in sink traps and drains. WGS confirmed the epidemiological link between clinical and environmental strains and the monoclonal pattern of the outbreak. After removing sinks from patient rooms and implementation of waterless patient care, no new acquisition was detected in the ICU within 8 months after the intervention.

Discussion: Implementation of waterless patient care with removal of the sinks in patient rooms was successful for termination of a PA-VIM ICU outbreak linked to multiple environmental water sources. WGS provides highly discriminatory accuracy to investigate environment-related outbreaks.

Keywords: Aquatic reservoir; Carbapememase; Outbreak; Pseudomonas aeruginosa; Sink; VIM; Waterless; cgMLST.

PubMed Disclaimer

Conflict of interest statement

All authors have no conflict of interest to declare.

Figures

Fig. 1
Fig. 1
Epidemic curve of cases with infection and/or acquisition of Pseudomonas aeruginosa VIM in the intensive care unit (ICU). Between March 2018 and September 2020, 16 patients were newly colonized and/or infected with a P. aeruginosa producing VIM strain during their ICU stay. In October 2020, waterless patient care was implemented in the ICU with no new acquisition event in the ICU during the next 8 months
Fig. 2
Fig. 2
Map of the intensive care unit with the two subunits A and B. Sinks with samples positive for Pseudomonas aeruginosa VIM are filled in green. Sinks condemned are marked with a red forbidden sign. Bedrooms who hosted patients with newly P. aeruginosa VIM acquisition are marked with a green human symbol. PR: preparation room, WDR: waste disposal room, RR: rest room for healthcare workers
Fig. 3
Fig. 3
UPGMA similarity tree based on cgMLST analysis of 32 ST111 strains of Pseudomonas aeruginosa. The tree includes 19 clinical strains and 2 environmental strains (sinks drains) from HUG, 5 strains from UK, 5 strains from Besançon (France) and 1 strain from Lausanne (Switzerland). The strain number, its origin and date of sampling are mentioned. The 21 strains from HUG belong to the same cluster. From the 19 clinical strains from HUG, 16 belong to patients with a suspected source of acquisition in the ICU, 1 from a patient with suspected cross transmission outside ICU and 2 from patients with nosocomial but unknown source of acquisition
See this image and copyright information in PMC

References

    1. Zawacki A, O’Rourke E, Potter-Bynoe G, Macone A, Harbarth S, Goldmann D. An outbreak of Pseudomonas aeruginosa pneumonia and bloodstream infection associated with intermittent otitis externa in a healthcare worker. Infect Control Hosp Epidemiol. 2004;25(12):1083–1089. doi: 10.1086/502348. - DOI - PubMed
    1. Longtin Y, Troillet N, Touveneau S, Boillat N, Rimensberger P, Dharan S, et al. Pseudomonas aeruginosa outbreak in a pediatric intensive care unit linked to a humanitarian organization residential center. Pediatr Infect Dis J. 2010;29(3):233–237. doi: 10.1097/INF.0b013e3181bc24fb. - DOI - PubMed
    1. Tissot F, Blanc DS, Basset P, Zanetti G, Berger MM, Que Y-A, et al. New genotyping method discovers sustained nosocomial Pseudomonas aeruginosa outbreak in an intensive care burn unit. J Hosp Infect. 2016;94(1):2–7. doi: 10.1016/j.jhin.2016.05.011. - DOI - PubMed
    1. Stover CK, Pham XQ, Erwin AL, Mizoguchi SD, Warrener P, Hickey MJ, et al. Complete genome sequence of Pseudomonas aeruginosa PAO1, an opportunistic pathogen. Nature. 2000;406(6799):959–964. doi: 10.1038/35023079. - DOI - PubMed
    1. Simner PJ, Opene BNA, Chambers KK, Naumann ME, Carroll KC, Tamma PD. Carbapenemase detection among carbapenem-resistant glucose-nonfermenting gram-negative bacilli. J Clin Microbiol. 2017;55(9):2858–2864. doi: 10.1128/JCM.00775-17. - DOI - PMC - PubMed

MeSH terms

LinkOut - more resources