Screening of allochthonous microorganisms in drinking water and studies on the faecal-originated Escherichia coli isolate survival after chemical disinfection

Access to sufficient water and food of suitable quality is a prime requirement for the improvement and maintenance of public health. Waterborne diseases are typically caused by enteric pathogens which belong to the group of organisms transmitted by the faecal-oral route. In the course of our work, in order to determine the presence of allochthonous microorganisms water of dug wells and springs were microbiologically analysed. The selected nonbottled mineral and well-waters are widely consumed by local people. The survival of faecal coliforms was studied in selected water samples during storage at 4 °C and after desinfection with chloramine and iodine. The microbiological quality of the majority of the analysed well and spring waters is not acceptable. The faecal Escherichia coli was still present in the water samples after 8 and 10 days and presented higher resistance to chloramine, but not to iodine, than the Escherichia coli EC/2 strain chosen for comparison.