Diarrheogenic Escherechia coli in potable water sources of West Bengal, India

Diarrheal diseases are a major cause of morbidity and mortality in developing countries. Among the bacterial pathogens, diarrheagenic Escherichia coli are most frequently connected in cases with epidemic and endemic diarrhea worldwide. Environmental surveillance for monitoring of E.coli is very rare. In the present study, we have applied a modified technique to quantify coliform and E. coli in different potable water sources and their subsequent characterization (in relation to diarrheal pathogenicity) in the diarrhea endemic foci of West Bengal. More than one-fifth of the targeted sources (21.4%) have been identified harboring E. coli. Serotyping and molecular analysis reveals multidrug resistant EPEC, EIEC and ETEC among 9% of positive sources. Rainy season seems to be the most conducive period for E. coli induced diarrhea. While non-diarrheogenic E.coli were sensitive to most of the drugs, diarrheogenic E. coli, possessing toxicity, showed resistance against tetracycline, kanamycin, furazolidone, amoxicillin, ampicillin, norfloxacin, ciprofloxacin. Presence of multidrug resistant diarrheogenic E.coli justifies the potentiality of potable water sources as its vehicle and as a potent diarrheal inducer in diarrhea prone area along with increasing concern of drug resistance. Presence of diarrheogenic E. coli stresses the urgent need of its environmental surveillance like diarrheogenic Vibrios.