Prevalence and phenotypic characterization of ESBL producing E.coli and Klebsiella among the fecal isolates of normal population

Introduction: Prevalence of extended spectrum beta lactamase producing bacteria has been increasing worldwide despite of outbreak situations. ESBLs occupying the gastrointestinal tract are spread across other bacteria and humans through the environment. The present study is a report on the prevalence of ESBL producers among normal individuals of a rural population in south India. Materials and Methods: 1000 normal individuals were selected from the villages of Salem district. Stool samples were collected and processed in MacConkey agar plates supplemented with Cefotaxime 5ug/ml. Morphological and biochemical methods were used to identify the colonies initially. ESBL producing organisms were identified by Double Disk Synergy Test – DDST and Phenotypic Confirmatory Disk Diffusion test- PCDDT. Results: From the total number of samples, 37.9% has shown bacterial growth. The rate of ESBL producing Enterobacteriaceae was found to be 33.8% with E.coli (29.3%) being the predominant species followed by klebsiella (8.6%). Conclusion: The results of our study gives a brief information about the multidrug resistance and also the prevalence of ESBL producing bacteria in the community faecal flora. Phenotypic methods were successfully applied to screen large number of samples. The rate of ESBL producers in the community is notably high. Routine surveillance programmes and awareness of hygienic practices among the rural population are highly recommended to monitor and control the spread. Keywords: Beta lactams, E.coli, Enterobacteriaceae, Klebsiella.