总结
      城市洪水可能会因微生物病原体的动员和废水处理系统的溢流而对公众和环境健康造成重大风险。在这里，我们试图通过获得在佐治亚州亚特兰大市收集的洪水样本中存在的抗生素抗性基因（ARGs）、毒力因子（VFs）和病原体的宏基因组图谱来评估这种风险，这些样本被分为两组：干旱后发生的洪水和定期（季节性）降雨后发生的洪灾。尽管在我们测序工作的检测极限范围内没有出现主要的（已知的）病原体（~3 Gbp/sample），我们观察到干旱后的洪水显示出与雨天后的洪水相比，ARGs和VFs的丰度高2.5倍。这些差异主要源于假单胞菌属的几个新物种，它们在前者样品中比后者更具优势，并且除了ARGs和VFs外，还携带了几个应对渗透胁迫的基因。这些结果表明，在美国东南部的城市环境中，有一些以前未被描述的物种在洪水事件后被动员起来，这可能会增加公共健康风险，特别是在干旱时期之后，这需要进一步关注。
Summary
Urban floodwater could lead to significant risk for public and environmental health from mobilization of microbial pathogens and overflow of wastewater treatment systems. Here, we attempted to assess this risk by obtaining metagenomic profiles of antibiotic resistance genes (ARGs), virulence factors (VFs) and pathogens present in floodwater samples collected in urban Atlanta, GA that were categorized in two distinct groups: floods that occurred after periods of drought and those after regular (seasonal) rain events. Even though no major (known) pathogens were present at the limit of detection of our sequencing effort (~3 Gbp/sample), we observed that floodwaters after drought showed a 2.5-fold higher abundance of both ARGs and VFs compared to floodwater after rainy days. These differences were mainly derived by several novel species of the Pseudomonas genus, which were more dominant in the former versus the latter samples and carried several genes to cope with osmotic stress in addition to ARGs and VFs. These results revealed that there are previously undescribed species that become mobilized after flooding events in the Southeast US urban settings and could represent an increased public health risk, especially after periods of drought, which warrants further attention.

https://ami-journals.onlinelibrary.wiley.com/doi/abs/10.1111/1758-2229.13047