Antimicrobial-resistant in Escherichia coli isolated from different effluent locations within Ahmadu Bello University, Zaria, Nigeria

Abstract

The safety of municipal water is increasingly becoming of concern globally. Agricultural activities, industrial and residential effluents and community waste are ways through which water sources are contaminated and resistant bacteria can be spread via effluents to municipal water. The study aimed to isolate and determine the distribution of antimicrobial drug-resistant Escherichia coli from different points of the University sewer system in April 2018. A total of 48 samples were collected twice weekly from the six randomly selected inspection chamber sites out of the 14 identified sites. The selected sites of the sewer were located in some hostels, markets and health service areas within the ABU. main campus. The samples were processed by culturing on an EMB agar plate followed by biochemical characterization using conventional biochemical tests and Microbact 12E. An antimicrobial sensitivity test was also carried out using 13 different antibiotic discs. The results obtained revealed that the Community market had an isolation rate of 4(50%), while Sickbay had 3(37.5%) and Danfodiyo hostel with 2(25%). Multiple antimicrobial resistance index (MARI) was found to be 0.31 from four isolates (36%) of E. coli of which 3(75%) were sampled from Sickbay and 1(25%) from ABU Dam. Also, five isolates (45%) had MARI of 0.23, of which 2(40%) were sampled from Danfodiyo hostel, 1(20%) from Ribadu hostel and 2(40%) from Community market. The E. coli isolates were more resistant to Ampicillin, tetracycline and cephalothin. Other bacteria isolated were Klebsiella ozaenae, Hapnea alvei and Morganella morganii all with MARI of 0.31. There is a need for public health awareness on the effect of discharging antibiotic-resistant E. coli contaminated effluent into the environment and water bodies. Hence, the public health significance of recycling such water for domestic usage and agricultural purpose.