Fungal and Bacterial Contamination on Indoor Surfaces of a Hospital in Mexico

Nosocomial infections acquired during hospitalization depend on the characteristics of the microorganisms, with a high risk of these being acquired when the environment is contaminated. Cross-transmission of microorganisms by contaminated surfaces and the hands of health care workers are considered to be the main route of the spread of nosocomial infections and in many Mexican hospitals, information about microbial and fungi contaminants on indoor surfaces is insufficient. In this study, we explore the bacterial and fungal genera present on surfacestaken from; armrest beds, wash sinks, medical tables, and the hands of medical staff fromemergency, intensive care unit, inhalation therapy, stomatology and pediatric areas. The present study was conducted in a hospital located in Xalapa City in Mexico; the samples were taken during a 6 month period from August to December, 2010. Surface swab specimens were collected from predefined surfaces with cotton tipped applicators, pre-moistened with sterile saline and inoculated on Sabouraud dextrose or selective Eosin-Methylene Blue agar plates and incubated for 1 to 7 days at 28°C or 37°C in three triplications in order to isolate bacterial and fungal contaminants. We isolated and identified gram-negative bacteria and fungi and the results showed that the predominant bacteria were; Klebsiella spp. Pseudomonas spp. and E coli spp. The predominant genera of fungi were; Cladosporium spp. Microsporum canis., Aspergillusspp. and Penicillium spp. This study showed that all areas of the hospital have pathogenic fungi and bacteria, indicating that these are a potential source of cross-infection from the hands of health care workers to their patients.