FECES-TO-FARM: technologies and molecular tools for controlling the dissemination of antimicrobial resistance from humans to animals while recovering fertilizing nutrients******

作为全球头号公共卫生问题，抗生素耐药性的蔓延对人类健康、农业、环境和全球贸易都产生了深远的影响。动物生产是已知的可移动抗菌素耐药基因(ARGs)的扩增库，食品供应链可能是人类的主要途径(从农场到餐桌的途径)。最近的数据显示，人类和动物的ARGS谱的差异与肠道微生物群的差异有关。因此，释放到环境中的与人类相关的ARG可能比以前与人类微生物群无关的ARG更容易回归人类。使用废水处理后的剩余生物固体作为肥料，在城市废水和转移人类相关ARG的农场(粪便到农场的途径)之间建立了近乎直接的联系。因此，使用市政生物固体回收营养物质可能会加剧抗菌素耐药性危机。生物固体的产甲烷厌氧消化过程中的精氨酸动态(处置前的最后处理)仍然知之甚少，这排除了进一步开发以最大限度地减少精氨酸负荷的可能性。我们的战略项目将系统地评估促进消化的新的联合治疗，以确定最佳的ARG去除方法。将重点放在减少机制上，将选择联合处理，因为它们灭活微生物和降解抗菌剂(即物理化学处理)，或者因为它们改变微生物群落(例如，极端pH预发酵)。氟喹诺酮类药物(生物固体中的主要抗菌剂)将被量化，以评估它们对ARG动态的影响，并为监管机构提供新的社区定义的最低观测效应浓度(LOECs)，用于设定去除目标。同时，我们将与加拿大抗菌素耐药性监测机构合作，确定废水中比动物粪便中更丰富的ARG，作为粪便到农场的监测目标。这些关键数据将支持政府制定应对抵抗危机的政策。支持公司将获得增值知识，以改进他们的设备，并为新的市场限制做好准备。

As the number one global public health problem, the spread of antimicrobial resistance has profound impacts on human health, agriculture, the environment, and global trade. Animal production is a known amplification reservoir of mobile antimicrobial resistance genes (ARGs), with the food-supply chain likely being a major pathway to humans (FARM-to-FORK pathway). Recent data revealed that differences in ARGs profiles of human and animals correlated with differences in gut microbiomes. Thus, human-associated ARGs released to the environment may return to humans more readily than ARGs not previously associated with human microbiomes. The use of wastewater treatment residual biosolids as fertilizers creates a near direct link between municipal wastewaters and farms transferring human-associated ARGs (FECES-to-FARM pathway). Consequently, recycling nutrients using municipal biosolids may exacerbate the antimicrobial resistance crisis. ARG dynamics during methanogenic anaerobic digestion of biosolids (last treatment before disposal) remain poorly understood, precluding further developments to minimize ARG loads. Our Strategic Project will systematically assess new co-treatments that enhance digestion to determine the optimal ARG removal method. Focusing on reduction mechanisms, co-treatments will be selected either because they inactivate microbes and degrade antimicrobials (i.e., physicochemical treatments) or because they change microbial communities (e.g., extreme pH pre-fermentation). Fluoroquinolones (main antimicrobials in biosolids) will be quantified to evaluate their influence on ARG dynamics, and to provide regulators with novel community-defined lowest observed effect concentrations (LOECs) for setting removal targets. In parallel, our collaboration with the Canadian Antimicrobial Resistance Surveillance will identify ARGs that are more abundant in wastewater than in animal excrement to use as FECES-to-FARM monitoring targets. These key data will support governmental efforts to develop policies against the resistance crisis. Supporting companies will gain value-added knowledge to improve their equipments and their readiness for new market constraints.