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IntroductionNosocomial pathogens are responsible for severe infections and are typically acquired in healthcare settings within days of patient admission. One of the primary contributors to the spread of healthcare-associated infections (HAIs) is the transfer of bacteria from inanimate surfaces to patients.MethodsA cross-sectional study was done at Zewditu Memorial Hospital from June to November 2024. For this study, 204 inanimate surfaces from operating rooms and intensive care units were swabbed and cultured on MacConkey and blood agar. Bacteria were identified based on their colony morphology, gram staining, and conventional biochemical tests. Antimicrobial susceptibility testing was done using disk diffusion. Extended-spectrum beta-lactamase (ESBL) producing gram-negative bacteria were confirmed phenotypically using the double disc synergy and combination disc methods, while carbapenemase producers were identified using the Modified Carbapenem inactivation method. Methicillin-resistant Staphylococcus aureus (MRSA) was detected via the Cefoxitin Disk Diffusion Test. A P-value of less than 0.05 was considered statistically significant. Data were analyzed using SPSS version 20.ResultsOf the 204 swabbed samples, 77.45% (n = 158/204) showed bacterial growth, yielding a total of 171 bacterial isolates. Among these, Gram-positive bacteria comprised 71.3% (n = 122/171), while Gram-negative bacteria accounted for 28.7% (n = 49/171). The most prevalent isolates were Coagulase-negative Staphylococcus (CoNS), making up 46.1% (n = 79/171), followed by Bacillus spp. at 21.6% (n = 37/171). Out of the total isolates, 55 were identified as pathogenic bacteria based on their potential to cause disease and selected for antibiotic resistance testing. P. aeruginosa 36.7% (n = 18/49), Acinetobacter spp. 16.3% (n = 8/49), E. coli 14.2% (n = 7/49) and S. aureus 4.9% (n = 6/122) were the commonest pathogenic bacteria identified. Gram-negative bacteria showed high resistance to ampicillin (67.3%), amoxicillin and clavulanic acid (61.2%), ciprofloxacin (63.2%), sulfamethoxazole-trimethoprim (63.2%), cefepime (57.1%), and piperacillin-tazobactam (55.1%). Similarly gram-positive bacteria showed high resistance to azithromycin (100%), penicillin (100%), clindamycin (100%), and erythromycin (100%). Multidrug resistance was observed in 61.8% (n = 34/55) of the tested gram-negative and gram-positive isolates. The incidence of ESBL-producing and carbapenemase-producing bacteria among the suspected gram-negative bacteria was 26.5% (n=13/49) and 12.2% (n=6/49), respectively. The prevalence of MRSA was 50% (n=3/6).ConclusionThe study identified a significant presence of multidrug-resistant bacteria in the hospital environment and on inanimate surfaces, emphasizing the urgent need for effective infection prevention and control measures.引言：医院获得性病原体可引发严重感染，通常是患者入院数天内于医疗环境中获得的病原体。医疗保健相关感染（healthcare-associated infections, HAIs）传播的主要途径之一，是细菌从无生命表面转移至患者体内。 方法：本研究于2024年6月至11月在泽维基图纪念医院（Zewditu Memorial Hospital）开展横断面研究。研究人员对手术室与重症监护室的204处无生命表面进行拭子采样，随后在麦康凯琼脂与血琼脂上进行培养。根据菌落形态、革兰氏染色及常规生化试验对细菌进行鉴定。采用纸片扩散法开展抗菌药物敏感性试验。超广谱β-内酰胺酶（Extended-spectrum beta-lactamase, ESBL）阳性革兰阴性菌通过双纸片协同试验与复合纸片试验进行表型确认，碳青霉烯酶产生菌则采用改良碳青霉烯灭活试验进行鉴定。耐甲氧西林金黄色葡萄球菌（Methicillin-resistant Staphylococcus aureus, MRSA）通过头孢西丁纸片扩散试验进行检测。以P值小于0.05作为具有统计学显著性的标准。采用SPSS 20.0版本对数据进行分析。 结果：204份拭子样本中，77.45%（n=158/204）检出细菌生长，共获得171株细菌分离株。其中革兰阳性菌占71.3%（n=122/171），革兰阴性菌占28.7%（n=49/171）。最常见的分离株为凝固酶阴性葡萄球菌（Coagulase-negative Staphylococcus, CoNS），占比46.1%（n=79/171），其次为芽孢杆菌属（Bacillus spp.），占比21.6%（n=37/171）。在所有分离株中，55株根据其致病潜力被鉴定为致病菌，并开展了抗生素耐药性检测。检出的常见致病菌包括：铜绿假单胞菌（P. aeruginosa）36.7%（n=18/49）、不动杆菌属（Acinetobacter spp.）16.3%（n=8/49）、大肠埃希菌（E. coli）14.2%（n=7/49）以及金黄色葡萄球菌（S. aureus）4.9%（n=6/122）。革兰阴性菌对氨苄西林（67.3%）、阿莫西林克拉维酸（61.2%）、环丙沙星（63.2%）、复方磺胺甲恶唑（63.2%）、头孢吡肟（57.1%）及哌拉西林他唑巴坦（55.1%）均表现出较高耐药性。革兰阳性菌对阿奇霉素、青霉素、克林霉素及红霉素的耐药率均达100%。在受试的革兰阳性与革兰阴性分离株中，61.8%（n=34/55）表现出多重耐药性。疑似革兰阴性菌中，产ESBL菌与产碳青霉烯酶菌的检出率分别为26.5%（n=13/49）与12.2%（n=6/49）。MRSA的检出率为50%（n=3/6）。 结论：本研究证实医院环境及无生命表面中存在大量多重耐药菌，凸显了落实有效感染预防与控制措施的迫切性。