Epidemiology of Bacterial Contamination of Inert Hospital Surfaces and Equipment in Critical and Non-critical Care Units: A Brazilian Study

Aims: 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 describe the epidemiology of bacterial contamination (contaminated sites, pathogen species and their antimicrobial susceptibility, and identifying of multidrug-resistant microorganisms - MDR) of inert hospital surfaces and medical equipment in two public hospitals in Northern Brazil.

Methods: This was a cross-sectional study with 243 samples (n = 208, from Hospital A; and n = 35, from Hospital B) collected by friction with humidified swabs from inert surfaces and equipment. Sequentially the samples were cultivated and bacterial species were identified by culture-based methods and tested for their susceptibility through agar diffusion assay according to the Clinical and Laboratory Standards Institute (CLSI).

Results: 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 (2.8%).

Conclusion: The failures in the control of bacterial contamination of inert surfaces and equipment in the two hospitals analyzed reinforce the need for a revised protocol for cleaning and disinfection of the inert surfaces and equipment, and for regulation of antibiotic dispensing, mainly in the AICU of Hospital A, which was found to be a reservoir of MDR pathogens.