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，抗菌药物耐药性的传播对人类健康、农业、环境和全球贸易产生深远影响。动物生产是已知的移动的抗菌素耐药基因（ARG）的扩增库，食物供应链可能是人类的主要途径（农场到餐桌途径）。最近的数据显示，人类和动物的ARGs谱的差异与肠道微生物组的差异相关。因此，释放到环境中的人类相关ARG可能比先前与人类微生物组无关的ARG更容易返回人类。使用废水处理残留的生物固体作为肥料，在城市废水和转移人类相关ARGs的农场之间建立了近乎直接的联系（FECES-to-FARM途径）。因此，利用城市生物固体回收营养物质可能会加剧抗菌素耐药性危机。生物固体产甲烷厌氧消化（处置前的最后处理）过程中的ARG动力学仍然知之甚少，阻碍了进一步的发展，以尽量减少ARG负荷。我们的战略项目将系统地评估增强消化的新的共处理，以确定最佳的ARG去除方法。关注还原机制，将选择共处理，因为它们抑制微生物并降解抗菌剂（即，物理化学处理）或因为它们改变了微生物群落（例如，极端pH预发酵）。将对氟喹诺酮类（生物固体中的主要抗菌剂）进行量化，以评估其对ARG动力学的影响，并为监管机构提供新的社区定义的最低观测效应浓度（LOEC），以设定清除目标。与此同时，我们与加拿大抗菌素耐药性监测机构的合作将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努力制定应对抵抗危机的政策。支持公司将获得增值知识，以改进其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.