Current microbiological water safety testing methods are not feasible in many settings because of laboratory, cost, and other constraints, particularly in low-income countries where water quality monitoring is most needed to protect public health. We evaluated two promising E. coli methods that may have potential in at-scale global water quality monitoring: a modified membrane filtration test followed by incubation on pre-prepared plates with dehydrated culture medium (CompactDry^TM), and 10 and 100 ml presence–absence tests using the open-source Aquatest medium (AT). We compared results to membrane filtration followed by incubation on MI agar as the standard test. We tested 315 samples in triplicate of drinking water in Bangalore, India, where E. coli counts by the standard method ranged from non-detect in 100 ml samples to TNTC (>200). Results suggest high sensitivity and specificity for E. coli detection of candidate tests compared with the standard method: sensitivity and specificity of the 100 ml AT test was 97% and 96% when incubated for 24 h at standard temperature and 97% and 97% when incubated 48 h at ambient temperatures (mean: 27 °C). Sensitivity and specificity of the CompactDry^TM test was >99 and 97% when incubated for 24 h at standard temperature and >99 and 97% when incubated 48 h at ambient temperatures. Good agreement between these candidate tests compared with the reference method suggests they are suitable for E. coli monitoring to indicate water safety.

由于实验室，成本和其他限制，当前的微生物水安全性测试方法在许多环境中都不可行，尤其是在最需要水质监测以保护公众健康的低收入国家中。我们评估了两种在大范围全球水质监测中可能具有潜力的大肠杆菌方法：改良的膜过滤测试，然后在预先制备的平板上与脱水培养基（CompactDry ^TM）一起孵育，并分别存在10和100 ml使用开源Aquatest介质（AT）进行缺勤测试。我们将结果与膜过滤比较，然后在MI琼脂上孵育作为标准测试。我们在印度的班加罗尔，那里饮用水的一式三份测试样品315大肠杆菌标准方法的计数范围从100 ml样品中未检出到TNTC（> 200）。结果表明，与标准方法相比，对候选测试的大肠杆菌检测具有更高的灵敏度和特异性：100 ml AT测试的灵敏度和特异性在标准温度下孵育24 h时分别为97％和96％，在标准温度下孵育24小时时为97％和97％。在环境温度（平均：27°C）下孵育48小时。在标准温度下孵育24小时时，CompactDry ^TM测试的灵敏度和特异性分别为> 99和97％，在环境温度下孵育48小时时为> 99和97％。与参考方法相比，这些候选测试之间的良好一致性表明它们适用于大肠杆菌监测以表明水的安全性。