How to control the dissemination of antibiotic resistance in the environment? A systematic review
Résumé
The massive use of antibiotics in human and animal health led to the emergence of antibiotic resistant bacteria (ARB). Antibiotic residues, ARB, their genes (ARG) as well as mobile genetic elements (MGE) are chronically introduced in aquatic and terrestrial environments by the discharge of wastewaters and organic wastes, directly or after treatment. The dynamics of ARG/MGE in these environmental reservoirs contributes to the dissemination of antibiotic resistance to pathogenic bacteria. The French Ministry of Ecological and Inclusive Transition commissioned a systematic review of literature on effective solutions to control the contamination of environment by ARB and ARG. According to published protocol [1] and One-Health approach, three sub-questions were addressed in this review to assess the effectiveness of 1) antibiotic use restriction, 2) treatments of wastewaters and organic wastes and 3) environmental management to reduce the environmental contamination by antibiotic resistance. Articles were analyzed through systematic map, qualitative and quantitative syntheses. After screening 17,798 articles from eight publication databases, 931 articles were included in the systematic map. While knowledge gaps were obtained for the 1st and 3rd sub-questions, a metaanalysis was carried out in sub-question 2 to determine effects of organic waste treatments on antibiotic resistance (126 studies, meta-regressions). Composting significantly reduced the relative abundance of ARG/MGE (84% removal, 27 studies, p < 0.05). Efficacy of anaerobic digestion is lower than composting with more heterogeneity in reducing ARG/MGE. The systematic review results will allow to: i) identify knowledge gaps for research (e.g., indicators of antibiotic resistance) and ii) develop recommendations for stakeholders and policy makers.