aeruginosa that persists on noncritical equipment and surfaces in a hospital. Results General level of contamination of the equipment in each ward The study included 4 of wards, sampled during 9 months, between February 2010 and September 2011. The find more samples were recovered from 10 cm2 area using a swab soaked in Tryptic Soy Broth. A total
of 290 environmental samples were analyzed for bacterial colonization. The samples were plated in Pseudomonas isolation agar medium (PIA) which is a selective medium used for the isolation of P. aeruginosa and other Pseudomonas species [25]. The number of colonies growing on PIA medium varied in the different equipment sampled. However, a pattern could be defined when considering three classes of level of contamination defined from the amount of counts obtained on PIA medium, based on the accuracy of plate counts enumeration [26]. The first level of contamination included equipment with less than 10 CFU per plate (low contaminated), 10 CFU per plate are considered the minimum CFUs for statistical significance, the second included equipment with CFU between 10 and 200 CFU per plate (medium contaminated), and the equipment with more than 200 CFU per plate were included in the third level (high contaminated), CFU counts over
200 are considered uncountable selleck due to spatial growth restrictions.The
percentage of equipment in each ward that showed low contamination level varied between 22% and 38% (Figure 1). Equipment with a surface number of CFU varying between 10 and 200 CFU were a minority in all wards (maximum 15%) and, in all wards, more than 50% of the equipment sampled had more than 200 CFU per sample. The level of colonization of the equipment was similar in the UCI compared to the Medicine I and II and Urology wards. Figure 1 Percentage of equipment with different levels of contamination. Low level contamination (blue), medium level of contamination (red) and high Wilson disease protein level of contamination (green). The majority of the samples collected in taps and sinks showed high level of contamination (Table 1). This pattern of contamination was observed during the 2 years of sampling. High level of contamination was also detected in the showers but in a low number of samples. On the other hand, contamination on surface Epoxomicin datasheet countertops and trays was detected only in spring samples (March 2010 and April 2011). The noncritical equipment manipulated mostly by the medical personnel as workbenches, stethoscopes and other medical equipment was either not contaminated or low contaminated (six samples in 2 years), but when the oxygen flask was found contaminated (one sample), the contamination level was high.