Antibiotic resistance has become a major threat to human health worldwide. Environment, particularly the water environment, has long been overlooked as a player in the antibiotic resistance cycle, although its role re...Antibiotic resistance has become a major threat to human health worldwide. Environment, particularly the water environment, has long been overlooked as a player in the antibiotic resistance cycle, although its role remains unclear. These can provide an ideal setting for the acquisition and dissemination of antibiotic resistance, as they are frequently affected by anthropogenic activities. The objective of this study was to establish a diffusion map of resistance integrons used as genetic markers of resistance associated with antibiotic resistance conferring genes (ARGs). Total DNA extracts from non-cultivable bacterial communities were used for the analyses. These communities were obtained from wastewater samples from 14 sites upstream and downstream of drainage channels or effluents in the cities of Abidjan, Bouaké, and Yamoussoukro. The results obtained correspond to the number of positives among the treated samples (n = 39). Among the genetic markers of dissemination, class 1 integrons were the most evident in 94.8% of samples in Abidjan (93.3%), Bouaké (100%) and Yamoussoukro (91.6%). Class 2 integrons and class 3 integrons were found respectively in 41% and 51% of all samples. Genes coding for β-lactamases and blaTEM was identified in almost all samples at a rate of 97.4%. A co-presence of the three genes blaTEM, blaSHV and blaCTX-M is also remarkable in the sites of the city of Yamoussoukro. Among the genes coding for carbapenemases, only blaKPC 17.94%, blaNDM 30.76% and blaOXA48 38.46% were detected in the samples.展开更多
The loads of organic matter, microorganisms, detergents and antibiotics in liquid hospital effluents make them complex environments, raising numerous health and ecological questions. Investigations of mycobacteria in ...The loads of organic matter, microorganisms, detergents and antibiotics in liquid hospital effluents make them complex environments, raising numerous health and ecological questions. Investigations of mycobacteria in water lack adequate techniques. This study is the first part of a pilot project aimed at developing an optimized protocol for the isolation of mycobacteria from hospital effluents, as a prelude to more in-depth investigation in this matrix. The aim was to compare the performance of two decontamination methods, three culture media and two incubation temperatures generally proposed in the literature, in order to identify the most effective methods in each case, as well as possible areas for improvement in the isolation of these germs from this environmental matrix. The results show that liquid hospital effluent can be decontaminated using both the NaOH method (4%;for 30 min.) and the CPC method (0.05%;for 30 min.), with the same mycobacteria recovery efficiency. Despite the low concentration, decontamination with CPC killed more mycobacteria and sufficiently eliminated contaminating germs. In contrast, decontamination with NaOH was less harmful to mycobacteria, but did not remove many contaminating germs. On the other hand, LJG medium performed better than LJGF medium and LJGP medium for the growth of mycobacteria in hospital waters. Finally, there was no difference in performance between the two incubation temperatures of 30℃ and 37℃. The results of this study show that further evaluation of existing protocols is required in order to optimize methods for the pre-treatment of hospital effluent for the isolation of mycobacteria.展开更多
文摘Antibiotic resistance has become a major threat to human health worldwide. Environment, particularly the water environment, has long been overlooked as a player in the antibiotic resistance cycle, although its role remains unclear. These can provide an ideal setting for the acquisition and dissemination of antibiotic resistance, as they are frequently affected by anthropogenic activities. The objective of this study was to establish a diffusion map of resistance integrons used as genetic markers of resistance associated with antibiotic resistance conferring genes (ARGs). Total DNA extracts from non-cultivable bacterial communities were used for the analyses. These communities were obtained from wastewater samples from 14 sites upstream and downstream of drainage channels or effluents in the cities of Abidjan, Bouaké, and Yamoussoukro. The results obtained correspond to the number of positives among the treated samples (n = 39). Among the genetic markers of dissemination, class 1 integrons were the most evident in 94.8% of samples in Abidjan (93.3%), Bouaké (100%) and Yamoussoukro (91.6%). Class 2 integrons and class 3 integrons were found respectively in 41% and 51% of all samples. Genes coding for β-lactamases and blaTEM was identified in almost all samples at a rate of 97.4%. A co-presence of the three genes blaTEM, blaSHV and blaCTX-M is also remarkable in the sites of the city of Yamoussoukro. Among the genes coding for carbapenemases, only blaKPC 17.94%, blaNDM 30.76% and blaOXA48 38.46% were detected in the samples.
文摘The loads of organic matter, microorganisms, detergents and antibiotics in liquid hospital effluents make them complex environments, raising numerous health and ecological questions. Investigations of mycobacteria in water lack adequate techniques. This study is the first part of a pilot project aimed at developing an optimized protocol for the isolation of mycobacteria from hospital effluents, as a prelude to more in-depth investigation in this matrix. The aim was to compare the performance of two decontamination methods, three culture media and two incubation temperatures generally proposed in the literature, in order to identify the most effective methods in each case, as well as possible areas for improvement in the isolation of these germs from this environmental matrix. The results show that liquid hospital effluent can be decontaminated using both the NaOH method (4%;for 30 min.) and the CPC method (0.05%;for 30 min.), with the same mycobacteria recovery efficiency. Despite the low concentration, decontamination with CPC killed more mycobacteria and sufficiently eliminated contaminating germs. In contrast, decontamination with NaOH was less harmful to mycobacteria, but did not remove many contaminating germs. On the other hand, LJG medium performed better than LJGF medium and LJGP medium for the growth of mycobacteria in hospital waters. Finally, there was no difference in performance between the two incubation temperatures of 30℃ and 37℃. The results of this study show that further evaluation of existing protocols is required in order to optimize methods for the pre-treatment of hospital effluent for the isolation of mycobacteria.
