Investigating the Probability of Water Coolers Contamination with Pseudomonas Aeruginosa in a number of Tehran Hospitals

Evaluation of the probability of water cooler contamination in hospitals to determine the water quality has important role in social safty. Pseudomonas Aeruginosa is considered as an opportunistic pathogen, since it is possible to grow with minimal nutritional requirements, it can grow in water bodies containing very little food such as tap water. This ability has led to their continuous presence in the hospital environment. The main objective of this study was to determine the rate of contamination in few of Tehran's hospitals water-cooling devices in terms of contamination with Pseudomonas Aeruginosa.

This is an experimental study and the stages of work were based on observation and test in the laboratory. Water samples were sampled in two seasons (autumn and winter) in 100 samples from five hospitals in different regions of Tehran. At first, the samples were transferred to the laboratory in a compartment filled with ice gel at 4 °C, and then the tubes containing different media were kept in an incubator at 37 °C for 24 to 48 hours. Then, the samples were examined for nutritional needs in terms of growth rate, carbohydrate usage by possible bacteria through oxidation or fermentation, glucose fermentation pathways, and determination of the bacterial power in the use of citrate, the presence of enzyme oxidase and catalase, the presence or absence of Enterobacteriaceae species and Salmonella was examined using culture media and specific tests. Data analysis was done descriptively using excel and SPSS software.

As a result of the research Bacillus species were identified. Also, in the tested specimens, pseudomonas susceptible to Aeruginosa species and the suspected alcaligenes species of Faecalis were also identified.

The temperature has a significant effect on the growth of the Pseudomonas Aeruginosa, and a high temperature of 37 °C leads to the increase in growth rate, and in low temperature of 4 °C during sunlight in cold weather (autumn and winter), the bacteria could not be detected in water coolers