Journal of Biosciences and Medicines, 2024, 12, 357-372 https://www.scirp.org/journal/jbm ISSN Online: 2327-509X ISSN Print: 2327-5081 DOI: 10.4236/jbm.2024.1211030 Nov. 20, 2024 357 Journal of Biosciences and Medicines Salmonella enterica and Escherichia coli Cohabitation among Factors Increasing Antibiotic Resistance in Bukavu City, Democratic Republic of the Congo Alain M. Okito 1,2* , John M. Wagacha 1 , Catherine Lukhoba 1 , Grace Waturu 3 , Alexi A. Lina 2 , Wolfgang R. Mukabana 1 1 Department of Biology, University of Nairobi, Nairobi, Kenya 2 Department of Biology, Université Officielle de Bukavu, Bukavu City, Democratic Republic of the Congo 3 Department of Microbiology and Immunology, University of Nairobi, Nairobi, Kenya Abstract Food- and water-borne diseases exacerbate cases of antimicrobial resistance (AMR), particularly in low- and middle-income countries. Since 2011, cases of enteric infections have been reported in Bukavu city, Democratic Republic of the Congo. The objectives of this study were to evaluate the rate of AMR and multidrug resistance (MDR) of Salmonella enterica and Escherichia coli, and to determine the effect of S. enterica and E. coli cohabitation on antibiotic resistance of S. enterica. Bacteria were isolated from 553 foods, milk, and water samples collected from restaurants, taps, tanks and wells in Bukavu. Microbial analyses involved bacterial culture, and morphological and biochemical char- acterization. Antibiotic susceptibility tests were performed before and after bacteria cohabitation of S. enterica and E. coli isolates in the same media. 152 (27.5%) and 27 (4.9%) of the samples tested positive for S. enterica and E. coli, respectively. Salmonella isolates were more susceptible to ciprofloxacin (75.7%) and co-trimoxazole (75.0%) and more resistant to ampicillin (82.2%). E. coli was more resistant to ciprofloxacin (59.3%). Overall, 90.5% of isolates (n = 179) were MDR. The origin (food, water) of S. enterica and E. coli isolates had no significant (p > 0.05) influence on their susceptibility to antibiotics. However, S. enterica isolates from milk were significantly (p = 0.00) antibiotic- resistant than those from food and water. The cohabitation between antibi- otic-susceptible S. enterica and antibiotic-resistant E. coli significantly (p < 0.00) increased the rate of antibiotic resistance of S. enterica from 30% to 89.5%, implying that interactions of antibiotic-resistant and antibiotic-susceptible How to cite this paper: Okito, A.M., Waga- cha, J.M., Lukhoba, C., Waturu, G., Lina, A.A. and Mukabana, W.R. (2024) Salmo- nella enterica and Escherichia coli Cohabi- tation among Factors Increasing Antibiotic Resistance in Bukavu City, Democratic Re- public of the Congo. Journal of Biosciences and Medicines, 12, 357-372. https://doi.org/10.4236/jbm.2024.1211030 Received: October 9, 2024 Accepted: November 17, 2024 Published: November 20, 2024 Copyright © 2024 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access