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Aim: In this study, we aimed to evaluate the survival of Salmonella typhi and Shigella flexneri, which have significance for public health, in various aqueous media (distilled water, 0.9% NaCl solution, chlorinated water) and at different temperatures. Materials and Methods: The water samples mentioned above were contaminated with approximately 5 x 105 bacteria/ml of S. typhi and S. flexneri, and then stored at 37 ºC, room temperature, in refrigerator (4 to 6 ºC) and in deep freezer (-20 ºC). From the water materials prepared accordingly, cultures were done beginning in the first 24 hours and later every other day for viability control of the bacteria until no growth was detected in three consecutive cultures. Results: We observed that S. flexneri in both 0.9% NaCl solution and distilled water survived the longest (87 and 83 days, respectively) when stored in the refrigerator. Similarly, S. typhi was found to be viable as long as 65 days in both 0.9% NaCl solution and distilled water, when stored in the refrigerator. No bacterial growth was determined in the cultures of chlorinated water samples stored at all four temperatures in the first 24 hours. Conclusions: We concluded that S. flexneri generally survived longer than S. typhi in the different water media. Having a prolonged survival of S. flexneri in aqueous media would present more risk than S. typhi for the transmission of waterborne infections.

Aim: The aim of the present study was to investigate the survival time of some nosocomial infectious agents on the surface of various covering materials. Materials and Methods: Four kinds of flooring materials (vinyl and ceramic tile as floor covering material; and laminate and inox sheet as bench covering material) were experimentally contaminated with Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and vancomycin-resistant (VR) Enterococcus faecalis, which were frequently encountered in nosocomial infections. The survival periods of representative agents on the tested flooring materials were detected by culturing from the surfaces. Results: It was found that the survival periods were shorter for all the tested bacteria on the vinyl surfaces, as compared to the ceramic surfaces; the difference was significant (P < 0.05). On the other hand, all the test bacteria survived shorter on the inox sheet than on the laminate surfaces (P < 0.05). On all of the 4 covering materials tested gram-positive bacteria were found to survive longer than the gram-negative ones. Conclusions: It was concluded that vinyl as flooring material and inox sheet as surface material for benches and laboratory tables may be preferred in order to reduce bacterial colonisation in the hospital environment.