Gram staining.

During June 2013 to October 2013, a total of 100 water samples were collected from various coastal regions of Trivandrum district, Kerala state, India. These samples were examined for the presence of pathogenic bacteria especially the pathogenic salmonella species. Water samples were collected in sterilized screw caped glass bottles, transported to the microbiology laboratory of Noorul Islam Institute of Medical Sciences, Neyyattinkara, Trivandrum, Kerala and processed according to the standard protocols for the identification of pathogenic Salmonella species, within 6 hours. The type of water included in the present study were pond water, river water, household water, well water, municipality supplied tap water and packaged bottled water. The present study revealed that the pond water, river water and household water were contaminated with pathogenic Salmonella species. The packaged bottled water and municipality supplied tap water devoid of Salmonella contamination. So based on the present study it is strongly suggested that water should be boiled before use or use packaged bottled water of good quality for drinking purposes.