Meriem Touati1, Linda Hadjadj2, Meryem Berrazeg3, Sophie Alexandra Baron2, Jean Marc Rolain2. 1. Laboratoire de Physiologie de la Nutrition et de Sécurité Alimentaire, Département de Biologie, Faculté des Sciences de la nature et de la vie, Université Oran 1, Oran 31000, Algeria; Aix-Marseille Université, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Faculté de Médecine et de Pharmacie, 19-21 boulevard Jean Moulin, 13385 Marseille Cedex 05, France. Electronic address: touati.meriem23@hotmail.fr. 2. Aix-Marseille Université, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Faculté de Médecine et de Pharmacie, 19-21 boulevard Jean Moulin, 13385 Marseille Cedex 05, France. 3. Unité de Microbiologie, Institut Pasteur d'Algérie, Antenne d'Oran, Oran 31000, Algeria; Département de Biologie, Faculté des Sciences de la nature et de la vie, Université Oran 1, Oran 31000, Algeria.
Abstract
OBJECTIVES: Colistin resistance has emerged worldwide, threatening the efficacy of colistin treatment of Gram-negative bacterial infections. Farms have been recognised as an important reservoir of genes conferring resistance to colistin. This study aimed to isolate and characterise colistin-resistant bacteria in farmlands located in the region of Oran, northwest Algeria. METHODS: Forty environmental samples were collected between May 2016 and March 2018 at eight agricultural sites in the Oran region. RESULTS: From the 40 samples, 103 colistin-resistant isolates were isolated from agricultural soil (n = 52), irrigation water (n = 31) and manure (n = 20). Eight isolates were identified as Escherichia coli, including six and two isolates carrying the mcr-1 and mcr-3 gene, respectively. All eight E. coli isolates were non-susceptible to amoxicillin, amoxicillin/clavulanic acid, ticarcillin, nalidixic acid, ciprofloxacin, gentamicin, trimethoprim/sulfamethoxazole and rifamycin; two were also non-susceptible to cefotaxime, cefepime and aztreonam and carried the blaTEM-12 gene in addition to mcr-1. The six mcr-1-carrying E. coli isolates (MIC ≥ 2 μg/mL) belonged to three sequences types, including ST10 (n = 3), ST405 (n = 2) and ST345 (n = 1), whereas the two mcr-3-carrying isolates were assigned to ST155. The conjugation assay was positive only for two mcr-1-positive isolates. CONCLUSION: These results show that farms are an important reservoir of colistin-resistant E. coli as well as other antimicrobial resistance genes such as ESBL genes. Transfer of manure from animals to soil and irrigation water might be disseminating a mix of multiple resistances, posing a worrying threat to human health.
OBJECTIVES: Colistin resistance has emerged worldwide, threatening the efficacy of colistin treatment of Gram-negative bacterial infections. Farms have been recognised as an important reservoir of genes conferring resistance to colistin. This study aimed to isolate and characterise colistin-resistant bacteria in farmlands located in the region of Oran, northwest Algeria. METHODS: Forty environmental samples were collected between May 2016 and March 2018 at eight agricultural sites in the Oran region. RESULTS: From the 40 samples, 103 colistin-resistant isolates were isolated from agricultural soil (n = 52), irrigation water (n = 31) and manure (n = 20). Eight isolates were identified as Escherichia coli, including six and two isolates carrying the mcr-1 and mcr-3 gene, respectively. All eight E. coli isolates were non-susceptible to amoxicillin, amoxicillin/clavulanic acid, ticarcillin, nalidixic acid, ciprofloxacin, gentamicin, trimethoprim/sulfamethoxazole and rifamycin; two were also non-susceptible to cefotaxime, cefepime and aztreonam and carried the blaTEM-12 gene in addition to mcr-1. The six mcr-1-carrying E. coli isolates (MIC ≥ 2 μg/mL) belonged to three sequences types, including ST10 (n = 3), ST405 (n = 2) and ST345 (n = 1), whereas the two mcr-3-carrying isolates were assigned to ST155. The conjugation assay was positive only for two mcr-1-positive isolates. CONCLUSION: These results show that farms are an important reservoir of colistin-resistant E. coli as well as other antimicrobial resistance genes such as ESBL genes. Transfer of manure from animals to soil and irrigation water might be disseminating a mix of multiple resistances, posing a worrying threat to human health.
Authors: Madubuike Umunna Anyanwu; Charles Odilichukwu R Okpala; Kennedy Foinkfu Chah; Vincent Shodeinde Shoyinka Journal: Biomed Res Int Date: 2021-01-22 Impact factor: 3.411
Authors: Madubuike Umunna Anyanwu; Ishmael Festus Jaja; Obichukwu Chisom Nwobi Journal: Int J Environ Res Public Health Date: 2020-02-06 Impact factor: 3.390