Prevalence of pathogenic and antibiotics resistant Escherichia coli from effluents of a slaughterhouse and a municipal wastewater treatment plant in Dakar

The aim of this study was to detect and characterize pathogenic and antibiotic resistant Escherichia coli isolated from slaughterhouse wastewater and the effluents of a municipal wastewater treatment plant (WWTP) in Dakar, Senegal. Genetic markers associated with enterohemorrhagic E. coli (EHEC) and extraintestinal pathogenic E. coli (ExPEC) were screened in 268 E. coli isolates from slaughterhouse and 272 E. coli isolates from WWTP. Concerning antimicrobial resistance, 40 E. coli isolates were studied for each of the two sampling sites. None of the E. coli isolates harboring the genes associated with EHEC was detected in WWTP. Of the 13 tested virulence genes, fuyA and f17 were the most prevalent. The pathogenic and resistant E. coli was found in the raw wastewater and the influent of slaughterhouse. The final rejection used for urban gardening, including the watering of vegetables does not contain E. coli. These results showed that, after treatment, the sanitation risks associated with the reuse water from WWTP were low. Key words: Escherichia coli, wastewater, enterohemorrhagic E. coli (EHEC), extraintestinal pathogenic E. coli (ExPEC), antimicrobial resistance, slaughterhouse.