Infection and Drug Resistance (Aug 2023)
Intensive Care Unit Sluice Room Sinks as Reservoirs and Sources of Potential Transmission of Carbapenem-Resistant Bacteria in a South African Tertiary Care Hospital
Abstract
Khelan R Dheda,1 Chad M Centner,2 Lindsay Wilson,3,4 Anil Pooran,3,4 Shireen Grimwood,2 Yonas T Ghebrekristos,2 Suzette Oelofse,3,4 Ivan A Joubert,5 Aliasgar Esmail,3,4 Michele Tomasicchio3,4 1Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa; 2Division of Medical Microbiology, National Health Laboratory Services (NHLS)/Groote Schuur Hospital, Microbiology, University of Cape Town, Cape Town, South Africa; 3Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town and UCT Lung Institute, Cape Town, South Africa; 4South African MRC/UCT Centre for the Study of Antimicrobial Resistance, University of Cape Town, Cape Town, South Africa; 5Division of Critical Care, Department of Anaesthesia and Perioperative Medicine, University of Cape Town, Cape Town, South AfricaCorrespondence: Michele Tomasicchio, Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town and UCT Lung Institute, Cape Town, South Africa, Tel +27 21 650 4331, Fax +27 21 650 3824, Email [email protected]: Carbapenem-resistant bacteria (CRB) pose a major health risk to patients in intensive care units (ICU) across African hospitals. There are hardly any data about the role of hospital sinks as reservoirs of CRB in resource-poor African settings. Furthermore, the specific within-sink location of the highest concentration of pathogens and the role of splash back as a transmission mechanism remains poorly clarified.Methods: We swabbed ICU sluice room sinks in a tertiary hospital in Cape Town, South Africa. Swabs were taken from four different parts of the sluice room sinks (tap-opening, trap, below the trap, and u-bend). Dilutions were prepared and plated on carbapenem-infused agar. Colonies were identified and drug resistance profiles were determined using a biochemical analyser. To evaluate the potential transmission from the sink, similar plates were placed at fixed distances from the sink when the tap was turned on and off.Results: CRB were isolated from the trap, water interface below the trap, and the u-bend (the latter harboured the highest density of CRB species). Five CRB, resistant to at least 7 antibiotic classes, were isolated including Pseudomonas, Klebsiella, Citrobacter, Serratia, and Providencia. CRB could be cultured from droplets that fell on agar-containing plates placed at a varying distance from the trap.Conclusion: There is a higher density of CRB in the u-bend of ICU sluice room sinks which can act as a potential source of transmission. The data inform targeted CRB transmission-interruption strategies in resource-poor settings.Keywords: carbapenem-resistant bacteria, multi drug resistant bacteria, sluice room sink, intensive care units, antimicrobial resistance
