INCREASED PREVALENCE OF COAGULASE-POSITIVE STAPHYLOCOCCUS AUREUS IN MUNICIPAL DRINKING WATER SUPPLIES
The current study was designed to study the occurrence, enumeration, seasonal prevalence, and characterization of S.aureus isolates recovered from municipal drinking water supplies of Neemuch, Madhya Pradesh. Towards this, samples were taken from three selected sites; Dam (n=24), Treatment Plant (n=24), and Municipal Tap (n=24), fortnightly for a period of 1 year. The samples were examined for the presence and enumeration of S.aureus on Mannitol salt agar by Direct Plating Method. Confirmation of presumptive S.aureus isolates was carried out by means of gram staining technique, and production of catalase and coagulase. Coagulase positive S.aureus was recovered from 100% of raw, 95.8% of treated and 100% of tap water samples analyzed, in numbers significantly different from the standard set by WHO and BIS (P<0.05). The presence and percentage of Coagulase positive S.aureus in water distributed to the consumers is alarming and presents a serious health concern. The quality of water that reaches the end-point users must be identical to that which left the treatment plant, however, in the present study the microbiological quality in terms of S.aureus counts, at the point of consumption was worse than at the plant (P<0.05). The results of present study suggest that water purification systems in developing countries need to be efficient in the manner that they produce a “safe product” at least, if not sterile and must ensure safe delivery of water at the tap of consumers.