Background & Objectives: Considering the effect of Pseudomonas aeroginosa on public health as one of the most important microorganisms in swimming pools, this study was conducted to assess the possibility of contamination of hot spring pools with this organism in Ardabil province.

  Methods: In this study, 195 specimens were investigated from all public hot spring pools of Ardabil province during April to September 2011 when the number of swimmers reaches its peak. Standard method was used to investigate the presence or absence of P. aeroginosa in the valume of 100 ml collected samples.

  Results: The rates of contamination with P. aeruginosa at different months were as follows: April 17.5%, May 22.5%, June 22.5%, July 25% and August 20%. There was no statistically significant difference for P. aeroginosa contamination within the months. However, a statistically significant difference was considered for P. aeroginosa among all locations (p<0.05).

  Conclusion: Totally, 22.9% of specimens revealed P. aeroginosa which is alarming. So, it is suggested that monitoring and disinfection the public hot spring pools should be considered more seriously. It is also necessary to limit the number swimmers in public hot spring pools to reduce burden of contamination.