Private well water systems in rural areas that are improperly maintained will result in poor drinking water quality, loss of water supply, and pose human health risk. The purpose of this study was to investigate the occurrence of fecal indicator bacteria (FIB) and opportunistic pathogens in private well water in rural areas surrounding New Orleans, Louisiana. Our results confirmed the ubiquitous nature of Legionella (86.7%) and mycobacteria (68.1%) in private well water in the study area, with gene concentration ranged from 0.60 to 5.53 and 0.67 to 5.95 Log₁₀ of GC/100 mL, respectively. Naegleria fowleri target sequence was detected in 16.8% and Escherichia coli was detected in 43.4% of the water samples. Total coliform, as well as Legionella and mycobacteria genetic markers' concentrations were significantly reduced by 3-minute flushing. Next-generation sequencing (NGS) data indicated that the abundance of bacterial species was significantly increased in water collected in kitchens compared with samples from wells directly. This study provided integrated knowledge on the persistence of pathogenic organisms in private well water. Further study is needed to explore the presence of clinical species of those opportunistic pathogens in private well water systems to elucidate the health risk.

农村地区的私人井水系统维护不当将导致饮用水质量差、供水中断，并对人类健康构成威胁。本研究的目的是调查路易斯安那州新奥尔良周边农村地区私人井水中粪便指示菌 (FIB) 和机会致病菌的发生情况。我们的结果证实了研究区私人井水中军团菌（86.7%）和分枝杆菌（68.1%）的普遍存在，基因浓度范围分别为 GC/100 mL 的 0.60 至 5.53 和 0.67 至 5.95 Log ₁₀。在 16.8%的水样中检测到福氏耐格里菌靶序列，在 43.4% 的水样中检测到大肠杆菌。总大肠菌群，以及冲洗 3 分钟后，军团菌和分枝杆菌遗传标记的浓度显着降低。下一代测序 (NGS) 数据表明，与直接从井中采集的样本相比，在厨房收集的水中细菌种类的丰度显着增加。这项研究提供了有关病原微生物在私人井水中持续存在的综合知识。需要进一步研究以探索私人井水系统中这些机会性病原体的临床物种的存在，以阐明健康风险。