Institute of Life and Environmental Sciences, University of Iceland, Reykjavík, Iceland.
Engineering Research Institute, University of Iceland, Reykjavík, Iceland.
Lett Appl Microbiol. 2020 Apr;70(4):282-289. doi: 10.1111/lam.13271. Epub 2020 Feb 3.
Outbreaks of viral gastroenteritis are often connected to contaminated drinking water. The assessment of the water quality relies on the cultivation of indicator bacteria, and little is known of the fate of viruses in groundwater, especially in arctic regions. In Iceland, the groundwater temperature is between 3 and 6°C. The aim of this study was to determine virus inactivation at low temperature in a groundwater microcosm and in a borehole in a postglacial lava field. Two phage species that are commonly used as surrogates for norovirus were used, MS2 and PhiX174. Dialysis bags were used for the samples, and a device was constructed to hold many samples at a time and protect the samples in the borehole. No significant decrease of infective PhiX174 phages in the borehole or of the MS2 phages in the microcosm was observed. A slightly significant decrease of PhiX174 in the microcosm was noticed, with one log reduction time of 476 days. On the other hand, a significant reduction in MS2 was found in the field test, where the time needed for 90% reduction was 12·5 days. The results showed that an infective virus can exist in groundwater for months or years in arctic regions and a great difference may exist between results from microcosm and field tests. SIGNIFICANCE AND IMPACT OF THE STUDY: This study reveals that arctic regions are highly sensitive to virus contamination as an infective virus may exist in groundwater for years at low temperature. The results also show that the virus inactivation observed in field tests may differ considerably from the inactivation observed in laboratory microcosms. The results emphasize the importance of large protection zones around drinking water intakes as well as good wastewater treatment so that the likelihood of faecal contamination of groundwater is reduced.
病毒性肠胃炎的爆发通常与受污染的饮用水有关。水质评估依赖于指示菌的培养，但人们对病毒在地下水中的命运知之甚少，尤其是在北极地区。在冰岛，地下水温度在 3 到 6°C 之间。本研究的目的是确定低温下地下水中病毒的失活情况，并在冰川后熔岩场的钻孔中进行研究。本研究使用了两种常用于诺如病毒替代物的噬菌体，即 MS2 和 PhiX174。使用透析袋进行样本分析，并构建了一种装置，可以同时容纳多个样本并保护钻孔中的样本。在钻孔中，PhiX174 噬菌体和微宇宙中的 MS2 噬菌体都没有明显减少。在微宇宙中，PhiX174 噬菌体略有减少，对数减少时间为 476 天。另一方面，在野外试验中发现 MS2 噬菌体显著减少，90%减少所需的时间为 12.5 天。结果表明，在北极地区，感染性病毒可能在地下水中存在数月甚至数年，并且微宇宙和野外试验的结果可能存在很大差异。研究的意义和影响：本研究表明，北极地区对病毒污染非常敏感，因为在低温下，感染性病毒可能在地下水中存在数年。结果还表明，野外试验中观察到的病毒失活情况可能与实验室微宇宙中观察到的失活情况有很大差异。这些结果强调了在饮用水入口周围设置大的保护区以及良好的废水处理的重要性，以降低地下水受粪便污染的可能性。
