Isolation Rate and Antimicrobial Susceptibility Profile Of Enterobacteriaceae Isolated From Wastewater of Jimma Medical Center, Jimma Southwest Ethiopia.

Abstract

Background: Globally, the emergence and spread of antibiotic resistance bacteria has been described as a complex public health challenge. Most hospitals and other clinical settings in developing countries lack wastewater treatment facilities, such untreated wastewater from their operations are discharged into water bodies without any form of treatment. This problem is more critical in low and medium income countries like Ethiopia in which financial resources for the health care system are low and are likely to be hardest hit by antimicrobial resistance (AMR) both in terms of public health impact and economic burden. Objective: To determine isolation rate and Antimicrobial susceptibility profile of Enterobacteriaceae isolated from wastewater of Jimma Medical Center, Southwest Ethiopia. Methods: A cross-sectional study was conducted from July to August 2022 on 60 hospital wastewater samples collected at different intervals during the study period. A convenient and “time composite-sampling” technique was applied to collect hospital wastewater. Isolation and identification of Enterobacteriaceae was performed based on standard bacteriological methods. Antimicrobial susceptibility tests were carried out using Kirby–Bauer disc diffusion method on Muller Hinton agar. Wastewater physicochemical quality was measured using standards methods. Data was analyzed using SPSS version 25.0 and Microsoft Excel. Chi-square (χ2) test was used to evaluate the relationship of dependent and in dependent variables. Result: Out of 60 samples, 55 (91.7%) samples were positive to one or more isolates and a total of 114 bacteria which are members of Enterobacteriaceae were isolated. The highest isolate within sampling unit was observed at Laboratory unit, Radiology unit, and Obstetrics and Gynecology ward and Pooled 22 (19.3%). The isolates were differentiated into seven genera. E.coli 31(51.7%) and Klebssiella spp. 27(45.0%) were the predominant bacterial isolates. Amoxicillin/Clavulinic acid (88.4%) showed highest resistance followed by Ampicillin (87.0%), Tetracycline (76.5%) and Trimethoprim/sulfamethoxazole (71.9%). Least resistance rates were observed against Meropenem (9.6%) and Chloramphenicol (20.2%). The majority of bacterial isolates 101/114(88.6%) were multidrug resistant (MDR). The highest average of Dissolved oxygen 0.95±0.04mg/l was recorded at Point1 and 0.94±0.04 mg/l Mixed2 (Laboratory unit, Radiology unit and Obstetrics and Gynecology ward). Highest mean of Electrical Conductivity (EC) 7799±991µs/cm were recorded from Kitchen room/Cafeteria, Laundry room and Surgical ward A), while the lowest EC 1921±1291µs/cm was recorded from Pooled. Conclusion: The hospital wastewater contains large amount of bacteria which are members of Enterobacteriaceae. The majority of bacterial isolates were resistance to commonly prescribed drugs and most of them are multidrug resistance, which become a reservoir of resistant bacterial isolate. Therefore, establishing wastewater treatment plant is essential