Background

Estimates of the effectiveness of water, sanitation, and hygiene (WASH) interventions that provide high levels of service on childhood diarrhoea are scarce. We aimed to provide up-to-date estimates on the burden of disease attributable to WASH and on the effects of different types of WASH interventions on childhood diarrhoea in low-income and middle-income countries (LMICs).

Methods

In this systematic review and meta-analysis, we updated previous reviews following their search strategy by searching MEDLINE, Embase, Scopus, Cochrane Library, and BIOSIS Citation Index for studies of basic WASH interventions and of WASH interventions providing a high level of service, published between Jan 1, 2016, and May 25, 2021. We included randomised and non-randomised controlled trials conducted at household or community level that matched exposure categories of the so-called service ladder approach of the Sustainable Development Goal (SDG) for WASH. Two reviewers independently extracted study-level data and assessed risk of bias using a modified Newcastle-Ottawa Scale and certainty of evidence using a modified Grading of Recommendations, Assessment, Development, and Evaluation approach. We analysed extracted relative risks (RRs) and 95% CIs using random-effects meta-analyses and meta-regression models. This study is registered with PROSPERO, CRD42016043164.

Findings

19 837 records were identified from the search, of which 124 studies were included, providing 83 water (62 616 children), 20 sanitation (40 799 children), and 41 hygiene (98 416 children) comparisons. Compared with untreated water from an unimproved source, risk of diarrhoea was reduced by up to 50% with water treated at point of use (POU): filtration (n=23 studies; RR 0·50 [95% CI 0·41–0·60]), solar treatment (n=13; 0·63 [0·50–0·80]), and chlorination (n=25; 0·66 [0·56–0·77]). Compared with an unimproved source, provision of an improved drinking water supply on premises with higher water quality reduced diarrhoea risk by 52% (n=2; 0·48 [0·26–0·87]). Overall, sanitation interventions reduced diarrhoea risk by 24% (0·76 [0·61–0·94]). Compared with unimproved sanitation, providing sewer connection reduced diarrhoea risk by 47% (n=5; 0·53 [0·30–0·93]). Promotion of handwashing with soap reduced diarrhoea risk by 30% (0·70 [0·64–0·76]).

Interpretation

WASH interventions reduced risk of diarrhoea in children in LMICs. Interventions supplying either water filtered at POU, higher water quality from an improved source on premises, or basic sanitation services with sewer connection were associated with increased reductions. Our results support higher service levels called for under SDG 6. Notably, no studies evaluated interventions that delivered access to safely managed WASH services, the level of service to which universal coverage by 2030 is committed under the SDG.

Funding

WHO, Foreign, Commonwealth & Development Office, and National Institute of Environmental Health Sciences.

中文翻译：

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改善饮用水、卫生设施和肥皂洗手的干预措施对低收入和中等收入地区儿童腹泻病风险的有效性：系统评价和荟萃分析

 背景

对于为儿童腹泻提供高水平服务的水、环境卫生和个人卫生 (WASH) 干预措施的有效性估计很少。我们的目的是提供关于 WASH 造成的疾病负担以及不同类型的 WASH 干预措施对低收入和中等收入国家 (LMIC) 儿童腹泻的影响的最新估计。

 方法

在本次系统综述和荟萃分析中，我们按照搜索策略更新了之前的综述，通过搜索 MEDLINE、Embase、Scopus、Cochrane 图书馆和 BIOSIS 引文索引来查找基本 WASH 干预措施和提供高水平服务的 WASH 干预措施的研究，已发表2016 年 1 月 1 日至 2021 年 5 月 25 日期间。我们纳入了在家庭或社区层面进行的随机和非随机对照试验，这些试验与 WASH 可持续发展目标 (SDG) 的所谓服务阶梯方法的暴露类别相匹配。两名评审员独立提取研究水平的数据，并使用修改后的纽卡斯尔-渥太华量表评估偏倚风险，并使用修改后的建议分级、评估、制定和评价方法评估证据的确定性。我们使用随机效应荟萃分析和荟萃回归模型分析了提取的相对风险 (RR) 和 95% CI。本研究已在 PROSPERO 注册，CRD42016043164。

 发现

通过检索确定了 19 837 条记录，其中纳入了 124 项研究，提供了 83 项水​​（62 616 名儿童）、20 项卫生设施（40 799 名儿童）和 41 项个人卫生（98 416 名儿童）比较。与来自未经改进的水源的未经处理的水相比，使用使用点 (POU) 进行过滤处理的水，腹泻风险降低高达 50%（n=23 项研究；RR 0·50 [95% CI 0·41–0] ·60]）、日晒处理（n=13；0·63 [0·50–0·80]）和氯化（n=25；0·66 [0·56–0·77]）。与未改善的水源相比，在水质较高的场所提供改善的饮用水供应可将腹泻风险降低 52% (n=2; 0·48 [0·26–0·87])。总体而言，卫生干预措施将腹泻风险降低了 24% (0·76 [0·61–0·94])。与未改善的卫生设施相比，提供下水道连接可将腹泻风险降低 47% (n=5; 0·53 [0·30–0·93])。提倡用肥皂洗手可将腹泻风险降低 30% (0·70 [0·64–0·76])。

 解释

WASH 干预措施降低了中低收入国家儿童腹泻的风险。提供在 POU 过滤的水、通过改进的场所内水源提供更高的水质或通过下水道连接提供基本卫生服务的干预措施与减少量的增加有关。我们的结果支持可持续发展目标 6 所要求的更高服务水平。值得注意的是，没有研究评估提供安全管理的 WASH 服务的干预措施，即可持续发展目标下承诺到 2030 年实现全民覆盖的服务水平。

 资金

世界卫生组织、外交部、英联邦与发展办公室和国家环境健康科学研究所。