Exposure to enteric pathogens in the environment poses a serious risk for infection and disease. The accurate detection and quantification of enteric pathogens in environmental samples is critical for understanding pathogen transport and fate and developing risk assessment models. In this study, we successfully applied TaqMan real-time PCR assays to quantitatively detect five human-specific pathogens (Shigella/EIEC, Salmonella Typhi, Vibrio cholera, Norovirus, and Giardia) in samples from open drains, canals, floodwater, septic tanks, and anaerobic baffled reactors (ABR) collected in Mirpur, Dhaka, Bangladesh from April to October 2019. Overall, the grab and sediment samples showed low inhibition but the ultrafiltration samples collected from open drain had significantly higher (P = 0.0049) degree of PCR inhibition (median Ct = 31.06) compared to the extraction controls (Ct = 28.54). We developed a two-step method to adjust underestimation of pathogen quantities due to PCR inhibition and non-optimum PCR efficiency. Compared to other sample types, ultrafiltration samples demonstrated a wide range of concentration increase (1.0%–182.5%) by pathogens after adjusting for PCR inhibition and non-optimum efficiencies. These quantitative qPCR assays are successful in quantifying multiple enteric pathogens in environmental samples, and the adjustment method would be useful for correcting underestimates of pathogen quantities due to partial PCR inhibition and non-optimum efficiency.

暴露于环境中的肠道病原体会导致感染和疾病的严重风险。环境样本中肠道病原体的准确检测和定量对于了解病原体的运输和归宿以及开发风险评估模型至关重要。在这项研究中，我们成功地应用 TaqMan 实时荧光定量 PCR 检测来定量检测五种人类特异性病原体（志贺氏菌/EIEC、伤寒沙门氏菌、霍乱弧菌、诺如病毒和贾第鞭毛虫）) 在 2019 年 4 月至 2019 年 4 月至 2019 年 10 月在孟加拉国达卡米尔普尔收集的明渠、运河、洪水、化粪池和厌氧挡板反应器 (ABR) 的样品中。总体而言，抓斗和沉积物样品显示出低抑制作用，但从与提取 对照 ( Ct _ = 28.54)。我们开发了一种两步法来调整由于 PCR 抑制和非最佳 PCR 效率而导致的病原体数量的低估。与其他样品类型相比，在对 PCR 抑制和非最佳效率进行调整后，超滤样品显示出病原体的广泛浓度增加 (1.0%–182.5%)。这些定量 qPCR 测定成功地量化了环境样品中的多种肠道病原体，并且调整方法将有助于纠正由于部分 PCR 抑制和非最佳效率而导致的病原体数量的低估。