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bioRxiv · 10.1101/793034

Epidemiology of bacterial contamination of inert hospital surfaces and equipment in critical and non-critical care units: a Brazilian multicenter study

Abstract

The hospital environment is an important reservoir of microorganisms, including multidrug-resistant pathogens, which can cause in-patient contamination and healthcare-related infections. The objective of this study was to analyze the epidemiology of bacterial contamination (contaminated sites, pathogen species and their antimicrobial susceptibility, and tracking of multidrug-resistant microorganisms - MDR) of inert hospital surfaces and medical equipment in two public hospitals in Northern Brazil. This was a cross-sectional study with 243 samples (n = 208, from Hospital A; and n = 35, from Hospital B) collected by friction with swabs moistened in Brain Heart Infusion from inert surfaces and equipment. The samples were cultivated and bacterial species were identified by the classical approach and tested for their susceptibility through agar diffusion assay according to the Clinical and Laboratory Standards Institute (CLSI). Most inert surfaces and equipment analyzed presented bacterial contamination (95.5%). Staphylococcus aureus was the main pathogen of clinical significance detected both in Hospital A (61.8%) and B (68.6%). Hospital A showed higher rates of isolated MDR bacteria than Hospital B, especially in the Adult Intensive Care Unit, which included methicillin-resistant Staphylococcus aureus (MRSA) (52.7%), Enterobacteria resistant to 4th generation cephalosporins (19.4%), and multidrug-resistant Pseudomonas aeruginosa (2.78%). The failures in the prevention and control of infections in the two hospitals analyzed reinforce the need for a revised protocol for cleaning and disinfection of inert surfaces and medical equipment, and for regulation of antibiotic dispensing, mainly in the AICU of Hospital A, which was found to be a reservoir of MDR pathogens. This study is innovative because it is the pioneer in Western Bahia that describes the epidemiology of contamination of hospital surfaces, opportuning futures studies in this field.

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BibTeXRIS

Rodrigues, D. O., Peixoto, L. P., Barros, E. T. M., Guimaraes, J. R., Gontijo, B. C., Almeida, J. L., Azevedo, L. G., Lima, J. C. O., Camara, D. S.. 2019-10-13. Epidemiology of bacterial contamination of inert hospital surfaces and equipment in critical and non-critical care units: a Brazilian multicenter study. https://doi.org/10.1101/793034

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