Tesfaye AdmassuMisganu Yadesa2026-08-122026-08-122026https://etd.aau.edu.et/handle/123456789/8858Antimicrobial resistance (AMR) is a major global public health threat driven by inappropriate antimicrobial use and the emergence of resistant organisms. In Ethiopia, AMR-associated deaths are estimated to reach 89,200 by 2030. Therefore, to assess the presence of resistant bacteria and their associated genes in hospital environments, a cross-sectional study was conducted between October 2023 and October 2025 in Addis Ababa, Ethiopia. A total of 38 samples were collected from wastewaters (WW) and inanimate surfaces (IS) of Tikur Anbessa Specialized Hospital (TASH) and Zewuditu Memorial Hospital (ZMH). Samples were processed using culture-based methods, biochemical testing, and MALDI-TOF MS (EXS3000) for bacterial identification. Antimicrobial susceptibility was determined by the Kirby–Bauer disk diffusion method, while antimicrobial resistance genes (ARGs) detected by polymerase chain reaction (PCR). A total of 92 bacterial isolates were identified, comprising 63 (68.5%) from IS and 29 (31.5%) from WW samples. Among Gram-negative bacteria, 100% of K. pneumoniae isolates exhibited a multidrug-resistant (MDR) phenotype, while 89% of S. aureus were MDR from Gram-positive. The PCR revealed high frequencies of both chromosomal and plasmid-mediated ARGs. The most frequent chromosomal genes detected were blaTEM (94%), sul1 (53%), blaCITM (38.5%) and blaCTXM (37.5%), while high frequent plasmid-mediated ARGs were blaTEM (92%), tetA (65.6%), sul1 (56%), blaCTXM (50%), blaNDM (43.8%) and less frequent genes included blaOXA-48, blaKPC, blaFOXM, blaEBCM, blaMOXM, blaDHAM and ermB. Data analysis (SPSS v.26) indicated significant association (p < 0.05) between phenotypic resistance and the presence of specific carbapenamase genes. The findings indicate a high burden of AMR in hospital environments and highlight the importance of implementing on-site hospital WW treatment and strengthening surface disinfection practices to reduce the spread of AMR.en-USantimicrobial resistancehospital wastewaterantimicrobial resistance geneshospital inanimate surfaceEthiopiaThesis