The bag-mediated filtration system (BMFS) was developed to facilitate poliovirus (PV) environmental surveillance, a supplement to acute flaccid paralysis surveillance in PV eradication efforts. From April to September 2015, environmental samples were collected from four sites in Nairobi, Kenya, and processed using two collection/concentration methodologies: BMFS (> 3 L filtered) and grab sample (1 L collected; 0.5 L concentrated) with two-phase separation. BMFS and two-phase samples were analyzed for PV by the standard World Health Organization poliovirus isolation algorithm followed by intratypic differentiation. BMFS samples were also analyzed by a cell culture independent real-time reverse transcription polymerase chain reaction (rRT-PCR) and an alternative cell culture method (integrated cell culture-rRT-PCR with PLC/PRF/5, L20B, and BGM cell lines). Sabin polioviruses were detected in a majority of samples using BMFS (37/42) and two-phase separation (32/42). There was statistically more frequent detection of Sabin-like PV type 3 in samples concentrated with BMFS (22/42) than by two-phase separation (14/42, p = 0.035), possibly due to greater effective volume assayed (870 mL vs. 150 mL). Despite this effective volume assayed, there was no statistical difference in Sabin-like PV type 1 and Sabin-like PV type 2 detection between these methods (9/42 vs. 8/42, p = 0.80 and 27/42 vs. 32/42, p = 0.18, respectively). This study demonstrated that BMFS can be used for PV environmental surveillance and established a feasible study design for future research.

中文翻译：

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袋介导过滤系统在肯尼亚脊髓灰质炎病毒环境监测中的可行性。

袋介导过滤系统（BMFS）的开发是为了促进脊髓灰质炎病毒（PV）的环境监测，这是对根除PV的急性弛缓性麻痹监测的补充。从2015年4月至9月，从肯尼亚内罗毕的四个地点收集了环境样品，并使用两种收集/浓缩方法进行了处理：BMFS（> 3 L过滤）和抓取样品（1 L收集； 0.5 L浓缩）分两阶段进行分离。通过标准的世界卫生组织脊髓灰质炎病毒隔离算法对BMFS和两相样品进行PV分析，然后进行典型分型。还通过不依赖细胞培养的实时逆转录聚合酶链反应（rRT-PCR）和另一种细胞培养方法（将细胞培养-rRT-PCR与PLC / PRF / 5，L20B，和BGM细胞系）。使用BMFS（37/42）和两相分离（32/42）在大多数样品中检测到沙宾脊髓灰质炎病毒。从统计学上讲，用BMFS（22/42）浓缩的样品比通过两相分离（14/42，p  = 0.035），可能是由于测定的有效体积更大（870 mL对150 mL）。尽管测定了这种有效体积，但在这些方法之间，类似Sabin的PV 1型和类似Sabin的PV 2型检测没有统计学差异（9/42 vs. 8  /42 ，p = 0.80和27/42 vs. 32 / 42，p 分别为0.18）。这项研究表明，BMFS可用于光伏环境监测，并为将来的研究建立了可行的研究设计。