L growther, J Hena, I Sagayaraj, K Kishore, V Kumar
L growther, J Hena, I Sagayaraj, K Kishore, V Kumar. Enterotoxigenic E.coli In Coimbatore Drinking Water. The Internet Journal of Microbiology. 2008 Volume 7 Number 2.
Water is one of the potential carriers of pathogenic microorganisms and can endanger health and life of humans and animals. About 50% of deaths (4.6 million) in children under 5 years of age occur due to diarrhoeal diseases caused by drinking polluted water1. Kudoh and Zen-Yoji2 Studied 7 outbreaks of diarrhoea caused by
Current safe drinking water act regulations require the analysis of potable water for total coliforms, a group of closely related bacteria in the family enterobacteriaceae. Two quantitative methods are presently certified for this analysis, the Multiple Tube Fermentation (MTF) and the Membrane Filter (MF) technique6. Coliforms are historically used as indicator microorganisms to serve as a measure of fecal contamination and thus potentially of the presence of enteric pathogens in drinking water.
Results and Discussion
A total of 150 water samples were collected randomly from municipal water supplies in sterilized screw capped bottles, transported to the laboratory in cold condition and processed within 6 hours of their collection. The bacteriological examination according to American Public Health Association (APHA) included indicator of fecal pollution such as Total Coliforms (TC), Fecal Coliforms (FC) and Fecal Streptococci (FS). TC and FC were estimated by MTF method using lactose broth. FS were also estimated by MTF method using azide dextrose broth. The tubes for TC and FS tests were incubated at 37C and for FC test at 44.5 C. Suspensions from positive TC tubes (gas production in the inverted Durham’s tubes) were streaked on Eosin Methylene Blue (EMB) agar and Mac Conkey agar and incubated at 37C for 24-48 hours. Colonies showing typical characteristics of
The mean values of TC, FC and FS were 53.5, 20.5 and 15.2/
At the NSEC, Central Research Institute, except one all the isolates were identified into 11 already known serogroups (Table.1). One isolate could not be identified with any of these already existing serogroups. The serogroups O20, O69 and O153 occurred frequently. Isolation of O148, O153, O25 and O168 are of special importance since they are well known Enterotoxigenic
With increasing industrialization, water sources available for consumption and recreations have been adulterated with industrial as well as animal and human wastes. As a result water becomes a formidable factor in disease transmission. A defective water delivery system and inadequate environmental sanitation were a potential source of contamination of drinking water. Hence, this study suggests proper disinfection measures must be carried out in the municipal water supplies.
The authors are thankful to the Director, National