Carhuallanqui Andrea, Villafana Lorena, Gonzalez-Veliz Rosa, Cobo-Díaz José F, Álvarez-Ordoñez Avelino, Ramos-Delgado Daphne Doris
Public Health and Environmental Health Laboratory, Universidad Nacional Mayor de San Marcos, Lima 15081, Peru.
Avian Pathology Laboratory, Universidad Nacional Mayor de San Marcos, Lima 15081, Peru.
Antibiotics (Basel). 2025 Aug 10;14(8):818. doi: 10.3390/antibiotics14080818.
Pigs and cattle have been implicated as reservoirs of antimicrobial resistance genes (ARGs) that can spread to humans, and houseflies are considered potential carriers of bacteria with ARGs that could contribute to their spread to the environment, including food, animals, and humans. In this study, 107, 145, and 127 strains were isolated from houseflies, pigs, and cattle, respectively, from a slaughterhouse in Lima, Peru. Antimicrobial susceptibility testing was performed using the Kirby-Bauer method, where thirteen antibiotics were used. Strains were also plated on CHROMagar COL-APSE agar, and colistin's minimum inhibitory concentration (MIC) was determined. Colistin-resistant strains were subjected to whole genome sequencing. 7.8% (8/107), 1.38% (2/145), and 0.79% (1/127) of strains isolated from houseflies, pigs, and cattle, respectively, were resistant to colistin (MIC ≥ 4 µg/mL). ARGs associated with resistance to more than 6 different antibiotic classes were identified, including tetracyclines, beta-lactams, fluoroquinolones, nitroimidazoles, trimethoprim and amphenicols. This study suggests that flies could contribute to the dissemination of ARG carrying bacteria and shows the potential risk of animals and meat production systems as reservoirs of ARG carrying bacteria.
猪和牛被认为是抗菌药物耐药基因（ARGs）的储存宿主，这些基因可传播给人类，而家蝇被视为携带ARGs细菌的潜在载体，这些细菌可能促使ARGs传播到包括食物、动物和人类在内的环境中。在本研究中，分别从秘鲁利马的一家屠宰场的家蝇、猪和牛中分离出107株、145株和127株菌株。使用 Kirby-Bauer 方法进行药敏试验，共使用了13种抗生素。菌株还接种在CHROMagar COL-APSE琼脂上，并测定了黏菌素的最低抑菌浓度（MIC）。对耐黏菌素的菌株进行全基因组测序。从家蝇、猪和牛中分离出的菌株中，分别有7.8%（8/107）、1.38%（2/145）和0.79%（1/127）对黏菌素耐药（MIC≥4µg/mL）。鉴定出了与对6种以上不同抗生素类别耐药相关的ARGs，包括四环素类、β-内酰胺类、氟喹诺酮类、硝基咪唑类、甲氧苄啶和氯霉素类。本研究表明，家蝇可能有助于携带ARGs细菌的传播，并显示出动物和肉类生产系统作为携带ARGs细菌储存宿主的潜在风险。
