摘要
      抗生素耐药性是对人类健康的全球性威胁。许多地表水资源是抗生素抗性基因（ARG）转移的环境热点，农业径流和人类 排泄物是ARG向水生系统转移的常见来源。在这里，我们量化了992个溪流样本中的粪便标记基因和ARGs，这些样本是在5年期间从上奥科尼流域（美国乔治亚州）的115个地点季节性收集的，该地区以农业和城市发展的梯度为特征。在人类（48%的样本）、反刍动物（55%）和家禽（19%）中发现了广泛的粪便污染，73%的样本对六种靶向ARG（ermB、tet（B）、blaCTX-M-1、blaKPC、blaSHV和qnrS）中的至少一种检测呈阳性。虽然ARG与人类粪便标志物密切相关，但许多高度污染的样本与污水排放口无关，污水排放口是粪便和ARG污染的预期来源。为了确定污染源，我们将ARG和粪便标记数据与整个流域的土地利用/土地覆盖和废水基础设施的地理空间数据进行了合成。这项新的分析发现，ARGs与样本流域内下水道密度、下水道长度和化粪池系统年龄的测量值之间存在很强的相关性，这表明老化的废水基础设施造成的粪便非点源污染可能是人为ARGs在环境中的重要传播者。
Abstract
Antibiotic resistance is a global threat to human health. Many surface water resources are environmental hotspots of antibiotic resistant gene (ARG) transfer, with agricultural runoff and human waste highlighted as common sources of ARGs to aquatic systems. Here we quantified fecal marker genes and ARGs in 992 stream water samples collected seasonally during a 5-year period from 115 sites across the Upper Oconee watershed (Georgia, USA), an area characterized by gradients of agricultural and urban development. Widespread fecal contamination was found from humans (48% of samples), ruminants (55%), and poultry (19%), and 73% of samples tested positive for at least one of the six targeted ARGs (ermB, tet(B), blaCTX-M-1, blaKPC, blaSHV, and qnrS). While ARGs were strongly correlated with human fecal markers, many highly contaminated samples were not associated with sewage outfalls, an expected source of fecal and ARG pollution. To determine sources of contamination, we synthesized ARG and fecal marker data with geospatial data on land use/land cover and wastewater infrastructure across the watershed. This novel analysis found strong correlations between ARGs and measures of sewer density, sewer length, and septic system age within sample watersheds, indicating non-point sources of fecal contamination from aging wastewater infrastructure can be critical disseminators of anthropogenic ARGs in the environment.

https://www.sciencedirect.com/science/article/abs/pii/S0043135422008004