Fecal contamination of drinking-water in low- and middle-income countries: a systematic review and meta-analysis.
Fecal contamination of drinking-water in low- and middle-income countries: a systematic review and meta-analysis.
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DOI：
10.1371/journal.pmed.1001644
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发表时间：
2014-05
期刊：
影响因子：
15.8
通讯作者：
Bartram J
中科院分区：
文献类型：
--
作者：
Bain R;Cronk R;Wright J;Yang H;Slaymaker T;Bartram J
罗伯特·贝恩（Robert Bain）及其同事进行了系统回顾和荟萃分析，以评估来自“改良”水源的水是否比“未改良”水源更不可能含有粪便污染，并发现使用“改良水源”提供了一定的卫生保护措施，但并不能确保水不受粪便污染。 请参阅本文后面的编辑摘要 获得安全饮用水是身体健康的基本要求，也是一项人权。世界卫生组织和联合国儿童基金会使用“改良水源的使用”作为指标来监测全球安全饮用水的获取情况，但并未考虑水质测量结果。我们的目标是确定来自“改良”水源的水是否比“未改良”水源更不可能含有粪便污染，并评估污染程度因水源类型和环境而异。中文、英语、法语、葡萄牙语和西班牙语的研究是从 PubMed 和 Web of Science 等在线数据库以及灰色文献中找到的。 1990 年至 2013 年 8 月期间发表的低收入和中等收入国家研究评估了饮用水中是否存在大肠杆菌或耐热大肠菌群 (TTC)，前提是将结果与特定水源类型相关联。总共纳入了 319 项研究，报告了 96,737 个水样。在给定研究中，“改进”源的污染几率比“未改进”源低得多（比值比 [OR] = 0.15 [0.10–0.21]，I2 = 80.3% [72.9–85.6]）。然而，在 191 项研究中，38% 的来自改进来源的样本中超过四分之一含有粪便污染。低收入国家（OR = 2.37 [1.52–3.71]；p<0.001）和农村地区（OR = 2.37 [1.47–3.81] p<0.001）的水源更有可能受到污染。研究很少报告储存的水质或卫生风险，也很少实现稳健的随机选择。由于不经常进行水采样以及饮用前水质恶化，安全性可能被高估。使用“改良水源”可以提供一定程度的卫生保护，但不能确保水不受粪便污染，水源类型或环境之间的水源也不一致。因此，国际估计大大夸大了安全饮用水的使用情况，并且没有充分反映获取方面的差异。加强监测战略将把卫生保护指标与水质措施结合起来。 请参阅本文后面的编辑摘要 获得清洁水对于人类健康至关重要。水对人类健康和福祉的重要性体现在联合国于 2010 年重申的水人权中，该权利赋予每个人“充足、安全、可接受、可实际获取且负担得起的水供个人和家庭使用”的权利。千年发展目标 (MDG) 的具体目标 7c 是实现普遍获得水的一个步骤，旨在将无法可持续获得安全饮用水的人口比例减半。联合监测项目（JMP——世界卫生组织和联合国儿童基金会的一项倡议）使用的帮助监测实现这一目标进展的指标之一是“使用改进的来源”。改进的水源包括将管道水输送到住宅、院子或地块，或立管、钻孔和受保护的挖井。未经改善的水源是那些不能保护水免受外界污染的水源，例如未受保护的井、未受保护的泉水和地表水。虽然这种简单的分类可能反映了既定的卫生保护原则，但该指标因未能充分反映安全性而受到批评，这表明由于没有考虑微生物水安全或更全面地考虑卫生状况，数十亿人报告的安全用水获取情况可能被高估。因此，研究人员进行了系统回顾和荟萃分析，以调查改良水源的水是否比未改良水源的水更不可能超出基于健康的微生物水质准则，以及微生物污染在水源类型之间、国家之间以及农村和城市地区之间存在多大程度的差异。研究人员全面检索了文献，寻找合适的研究来调查低收入和中等收入国家所有类型饮用水的粪便污染情况。研究人员纳入了通过适当技术收集的含有大肠杆菌或耐热大肠菌（世界卫生组织推荐的粪便污染指标）可提取数据的研究。作者还评估了研究的偏倚和质量，并使用统计方法（随机效应元回归）来调查水源粪便污染最常见的风险因素和环境。作者利用这些方法纳入了 319 项研究，报告了 96,737 个水样。大多数研究来自撒哈拉以南非洲、南亚或拉丁美洲和加勒比地区。他们发现，总体而言，在给定研究中，“改良”来源的污染几率（机会）远低于“未改良”来源（优势比 = 0.15）。然而，在 191 项研究中，有 38% 的来自改进来源的样本中超过四分之一含有粪便污染。特别是受保护的挖井很少会受到粪便污染。研究人员还发现，低收入国家和农村地区的水源更容易受到污染（两者的比值比均为 2.37）。这些发现表明，虽然来自改良水源的水比未经改良水源的水更不可能含有粪便污染，但它们并不总是安全的。这项研究还提供了证据，表明将“改善”与“安全”等同起来，获得安全水源的人数被大大夸大了，并表明世界上很大一部分人口使用不安全的水。由于研究很少报告储存的水质或卫生风险，这些研究结果的准确性可能有限。然而，这项研究的结果表明，2010 年全球疾病负担可能会通过假设改善水源的零风险而大大低估了腹泻疾病的负担，并且需要新的指标来评估安全饮用水的获取情况。因此，应更多地利用其他措施，例如卫生检查，以提供安全评估的补充手段，并帮助确定防止水污染的纠正措施。请通过此摘要的在线版本访问这些网站：http://dx.doi.org/10.1371/journal.pmed.1001644。 PLOS Medicine 出版了有关水和卫生设施的系列文章 世界卫生组织/联合国儿童基金会供水和卫生设施联合监测计划拥有广泛的信息，包括数据和国家档案 联合国水机制是负责所有淡水和卫生设施相关事务的机构间协调机制 联合国还提供有关享有水和卫生设施的人权的信息
Robert Bain and colleagues conduct a systematic review and meta-analysis to assess whether water from “improved” sources is less likely to contain fecal contamination than “unimproved” sources and find that access to an “improved source” provides a measure of sanitary protection but does not ensure water is free of fecal contamination. Please see later in the article for the Editors' Summary Access to safe drinking-water is a fundamental requirement for good health and is also a human right. Global access to safe drinking-water is monitored by WHO and UNICEF using as an indicator “use of an improved source,” which does not account for water quality measurements. Our objectives were to determine whether water from “improved” sources is less likely to contain fecal contamination than “unimproved” sources and to assess the extent to which contamination varies by source type and setting. Studies in Chinese, English, French, Portuguese, and Spanish were identified from online databases, including PubMed and Web of Science, and grey literature. Studies in low- and middle-income countries published between 1990 and August 2013 that assessed drinking-water for the presence of Escherichia coli or thermotolerant coliforms (TTC) were included provided they associated results with a particular source type. In total 319 studies were included, reporting on 96,737 water samples. The odds of contamination within a given study were considerably lower for “improved” sources than “unimproved” sources (odds ratio [OR] = 0.15 [0.10–0.21], I2 = 80.3% [72.9–85.6]). However over a quarter of samples from improved sources contained fecal contamination in 38% of 191 studies. Water sources in low-income countries (OR = 2.37 [1.52–3.71]; p<0.001) and rural areas (OR = 2.37 [1.47–3.81] p<0.001) were more likely to be contaminated. Studies rarely reported stored water quality or sanitary risks and few achieved robust random selection. Safety may be overestimated due to infrequent water sampling and deterioration in quality prior to consumption. Access to an “improved source” provides a measure of sanitary protection but does not ensure water is free of fecal contamination nor is it consistent between source types or settings. International estimates therefore greatly overstate use of safe drinking-water and do not fully reflect disparities in access. An enhanced monitoring strategy would combine indicators of sanitary protection with measures of water quality. Please see later in the article for the Editors' Summary Access to clean water is fundamental to human health. The importance of water to human health and wellbeing is encapsulated in the Human Right to Water, reaffirmed by the United Nations in 2010, which entitles everyone to “sufficient, safe, acceptable and physically accessible and affordable water for personal and domestic uses.” A step towards such universal access to water is Millennium Development Goal (MDG) target 7c that aims to halve the proportion of the population without sustainable access to safe drinking-water. One of the indicators to help monitor progress towards this target used by the Joint Monitoring Project (JMP—an initiative of the World Health Organization and UNICEF) is “use of an improved source.” Improved sources include piped water into a dwelling, yard, or plot, or a standpipe, borehole, and protected dug well. Unimproved sources are those that do not protect water from outside contamination, such as unprotected wells, unprotected springs, and surface waters. While this simple categorization may reflect established principles of sanitary protection, this indicator has been criticized for not adequately reflecting safety, suggesting that reported access to safe water might be overestimated by billions of people by not accounting for microbial water safety or more fully accounting for sanitary status. So the researchers conducted a systematic review and meta-analysis to investigate whether water from improved sources is less likely to exceed health-based guidelines for microbial water quality than water from unimproved sources and to what extent microbial contamination varies between source types, between countries, and between rural and urban areas. The researchers comprehensively searched the literature to find appropriate studies that investigated fecal contamination of all types of drinking-water in low and middle-income countries. The researchers included studies that contained extractable data on Escherichia coli or thermotolerant coliform (the WHO recommended indicators of fecal contamination) collected by appropriate techniques. The authors also assessed studies for bias and quality and used a statistical method (random effects meta-regression) to investigate risk factors and settings where fecal contamination of water sources was most common. Using these methods, the authors included 319 studies reporting on 96,737 water samples. Most studies were from sub-Saharan Africa, southern Asia, or Latin America and the Caribbean. They found that overall, the odds (chance) of contamination within a given study were considerably lower for “improved” sources than “unimproved” sources (odds ratio = 0.15). However, in 38% of 191 studies, over a quarter of samples from improved sources contained fecal contamination. In particular, protected dug wells were rarely free of fecal contamination. The researchers also found that water sources in low-income countries, and rural areas were more likely to be contaminated (both had odds ratios of 2.37). These findings show that while water from improved sources is less likely to contain fecal contamination than unimproved sources, they are not consistently safe. This study also provides evidence that by equating “improved” with “safe,” the number of people with access to a safe water source has been greatly overstated, and suggests that a large number and proportion of the world's population use unsafe water. As studies rarely reported stored water quality or sanitary risks, the accuracy of these findings may be limited. Nevertheless, the findings from this study suggest that the Global Burden of Disease 2010 may greatly underestimate diarrheal disease burden by assuming zero risk from improved water sources and that new indicators are needed to assess access to safe drinking water. Therefore, greater use should be made of other measures, such as sanitary inspections, to provide a complementary means of assessing safety and to help identify corrective actions to prevent water contamination. Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001644. PLOS Medicine has a published series on water and sanitation The WHO/UNICEF Joint Monitoring Programme for Water Supply and Sanitation has extensive information including data and country files UN Water is the inter-agency coordination mechanism for all freshwater and sanitation related matters The UN also provides information on the human right to water and sanitation
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影响因子：
2
作者：
Agard, L;Alexander, C;Adesiyun, A
通讯作者：
Adesiyun, A
影响因子：
11.4
作者：
Amini, Manouchehr;Mueller, Kim;Johnson, C. Annette
通讯作者：
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影响因子：
11.4
作者：
Amini, Manouchehr;Abbaspour, Karim C.;Johnson, C. Annette
通讯作者：
Johnson, C. Annette
影响因子：
9.9
作者：
Al-Khatib, Issam A.;Arafat, Hassan A.
通讯作者：
Arafat, Hassan A.
影响因子：
4.3
作者：
Al-Salaymeh, Adel;Al-Khatib, Issam A.;Arafat, Hassan A.
通讯作者：
Arafat, Hassan A.