School of Tropical Medicine and Global Health, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan.
Japan International Cooperation Agency, Tokyo, Japan.
Bull World Health Organ. 2022 Sep 1;100(9):534-543. doi: 10.2471/BLT.22.288646. Epub 2022 Jul 1.
To assess if water from improved sources are microbiologically safe in Niassa province, Mozambique, by examining the presence of total coliforms in different types of water sources.
We conducted a cross-sectional household survey in two rural districts of Niassa province during the dry season, from 21 August to 4 October 2019. We observed water sources and conducted microbiological water quality tests and structured household interviews.
We included 1313 households, of which 812 (61.8%) used water from an improved source. There was no significant difference in presence of total coliforms between water sampled at improved and unimproved water sources, 62.7% (509 samples) and 65.7% (329 samples), respectively (-value = 0.267). Households using improved water sources spent significantly longer time collecting water (59.1 minutes; standard deviation, SD: 55.2) than households using unimproved sources (49.8 minutes; SD: 58.0; -value < 0.001). A smaller proportion of households using improved sources had access to water sources available 24 hours per day than that of households using unimproved sources, 71.7% (582 households) versus 94.2% (472 households; -value < 0.001). Of the 240 households treating water collected from improved sources, 204 (85.4%) had total coliforms in their water, while treated water from 77 of 107 (72.0%) households collecting water from an unimproved source were contaminated.
Current access to an improved water source does not ensure microbiological safety of water and thereby using access as the proxy indicator for safe drinking and cooking water is questionable. Poor quality of water calls for the need for integration of water quality assessment into regular monitoring programmes.
通过检测不同类型水源中总大肠菌群的存在情况，评估莫桑比克尼亚萨省改良水源的微生物安全性。
我们在 2019 年 8 月 21 日至 10 月 4 日的旱季在尼亚萨省的两个农村地区进行了一项横断面家庭调查。我们观察了水源，并进行了微生物水质测试和结构化家庭访谈。
我们共纳入 1313 户家庭，其中 812 户（61.8%）使用改良水源供水。取自改良和未改良水源的水样中总大肠菌群的存在率无显著差异，分别为 62.7%（509 个样本）和 65.7%（329 个样本）（-值=0.267）。使用改良水源的家庭花费的取水时间明显长于使用未改良水源的家庭（59.1 分钟；标准差，SD：55.2）（-值<0.001）。与使用未改良水源的家庭相比，使用改良水源的家庭能够 24 小时随时获得水源的比例较小，分别为 71.7%（582 户）和 94.2%（472 户）（-值<0.001）。在 240 户对从改良水源收集的水进行处理的家庭中，有 204 户（85.4%）的水中含有总大肠菌群，而从 107 户（72.0%）收集未改良水源的家庭中处理过的水中有 77 户受到污染。
目前获得改良水源并不能确保水的微生物安全性，因此将获得水源作为安全饮水和烹饪用水的替代指标是值得怀疑的。水质较差需要将水质评估纳入常规监测计划。
