Rego Ryan, Watson Samuel, Alam Mohammad Atique Ul, Abdullah Syed Asif, Yunus Mohammad, Alam Imam Taskin, Chowdhury A S M Homuan Kabir, Haider S M Arefeen, Faruque Asg, Khan Azharul Islam, Hofer Timothy, Gill Paramjit, Islam Mohammad Sirajul, Lilford Richard
Center for Global Health Equity, University of Michigan at Ann Arbor, USA.
Center for Global Health, University of Warwick, UK.
EClinicalMedicine. 2021 Nov 20;42:101205. doi: 10.1016/j.eclinm.2021.101205. eCollection 2021 Dec.
Water, Sanitation, and Hygiene (WASH) systems aim to reduce the spread of enteric pathogens, particularly amongst children under five years old. The most common primary outcome of WASH trials is carer-reported diarrhoea. We evaluate different diarrhoea survey instruments as proxy markers of enteric pathogen presence in stool.
We recruited 800 community-based participants from the Cox's Bazar Displaced Person's Camp in Bangladesh, split evenly between the rainy (July/August 2020) and dry (November/December 2020) periods. Participants were randomized evenly into either a standard survey asking carers if their child under five years old has had diarrhoea in the past fortnight, or a pictorial survey asking carers to pick from a pictorial chart which stools their child under five years old has had in the past fortnight. We collected stools from a random sub-sample of 120. Stools were examined visually, and tested for proteins associated with enteric infection and 16 enteric pathogens. We calculated sensitivities and specificities for each survey type, visual examination, and proteins with respect to enteric pathogen presence.
The sensitivity of the standard survey for enteric pathogen presence was 0.49[95%CI:0.32,0.66] and the specificity was 0.65[0.41,0.85]. Similar sensitivities and specificities were observed for pictorial survey, visual inspection, and proteins.
While diarrhoea is an important sign in clinical practice it appears that it is a poor proxy for enteric pathogen presence in stool in epidemiological surveys. When enteric infection is of interest, this should be measured directly.
The project was funded by the National Institutes for Health Research Global Health Research Unit on Improving Health in Slums (16/136/87) and by the University of Warwick.
水、环境卫生与个人卫生（WASH）系统旨在减少肠道病原体的传播，尤其是在五岁以下儿童中。WASH试验最常见的主要结果是照料者报告的腹泻情况。我们评估了不同的腹泻调查工具，将其作为粪便中肠道病原体存在情况的替代指标。
我们从孟加拉国科克斯巴扎尔流离失所者营地招募了800名社区参与者，在雨季（2020年7月/8月）和旱季（2020年11月/12月）平均分配。参与者被平均随机分为两组，一组进行标准调查，询问照料者其五岁以下儿童在过去两周内是否腹泻；另一组进行图片调查，让照料者从图片图表中挑选其五岁以下儿童在过去两周内的粪便类型。我们从120名参与者的随机子样本中收集了粪便。对粪便进行了肉眼检查，并检测了与肠道感染相关的蛋白质和16种肠道病原体。我们计算了每种调查类型、肉眼检查和蛋白质对于肠道病原体存在情况的敏感性和特异性。
标准调查对于肠道病原体存在情况的敏感性为0.49[95%置信区间：0.32，0.66]，特异性为0.65[0.41，0.85]。图片调查、肉眼检查和蛋白质的敏感性和特异性与之相似。
虽然腹泻在临床实践中是一个重要体征，但在流行病学调查中，它似乎并不是粪便中肠道病原体存在情况的良好替代指标。当关注肠道感染时，应直接进行检测。
该项目由英国国家卫生研究院全球卫生研究组改善贫民窟健康项目（16/136/87）和华威大学资助。
