Effect of drinking water treatment on bacterial strain sharing among Kenyan children

总结 在腹泻和肠道感染率高的社区， 幼儿教育没有得到很好的研究。然而，了解这些传播模式是至关重要的知识 在资源有限的环境中选择和实施保护儿童健康的干预措施。 水处理干预措施往往针对家庭一级，但最近的大规模试验， 家庭一级的干预措施并没有一贯显示儿童腹泻流行率的下降。一 一种解释是，家庭一级的饮用水干预措施未能阻断社区传播 途径，导致儿童持续暴露于细菌病原体。在这里，我们将研究菌株共享 在多个空间尺度上，包括家庭内部和家庭之间， 城市和农村地区。我们将利用以前收集的（由我们的团队）粪便样本，从240套 兄弟姐妹（n=480名儿童），包括来自120个城市家庭和120个农村家庭的兄弟姐妹。无论是 城市和农村的研究地点，我们将有独特的机会，从相同数量的家庭抽样 从有和没有获得全社区饮用水氯化的村庄。我们将1）比较 肯尼亚农村与城市社区细菌菌株共享的规模; 2）评估 在城市和农村社区进行社区范围的氯化消毒，以实现细菌菌株共享。我们 研究人群还将使我们能够调查是否细菌菌株共享模式和社区范围内的水 治疗效果对年龄较小的学龄儿童和年龄较大的学龄儿童不同。我们将使用短读宏基因组 测序和一套新的创新的计算细菌菌株跟踪工具， 来实现这些目标。我们的研究结果将为未来饮用水和其他 应实施环境干预措施，如果实施旨在保护环境的干预措施， 农村和城市社区的幼儿接触细菌病原体的情况应该有所不同。

SUMMARY In communities with high rates of diarrhea and enteric infections, the spatial scale of bacterial strain sharing in young children has not been well studied. Yet, understanding these transmission patterns is critical knowledge for selecting and implementing interventions to protect child health in resource-constrained environments. Water treatment interventions are often targeted at the household level, yet recent large-scale trials of household-level interventions have not consistently shown reductions in child diarrhea prevalence. One explanation is that household-level drinking water interventions fail to disrupt community transmission pathways, resulting in continued child exposure to bacterial pathogens. Here, we will investigate strain sharing between child pairs at multiple spatial scales, including within households and between households across urban and rural settings. We will leverage previously collected (by our team) fecal samples from 240 sets of siblings (n=480 children), including siblings from 120 urban households and 120 rural households. In both urban and rural study sites, we will have the unique opportunity to sample from equal numbers of households from villages with and without access to community-wide drinking water chlorination. We will 1) compare the scale of bacterial strain sharing in rural versus urban communities in Kenya; and 2) evaluate the effect of access to community-wide chlorination on bacterial strain sharing in both urban and rural communities. Our study population will also allow us to investigate if bacterial strain sharing patterns and community-wide water treatment effects differ for younger versus older school-aged children. We will use short-read metagenomic sequencing and a new innovative suite of computational bacterial strain tracking tools developed by our team to achieve these aims. Our findings will inform the scope and scale at which future drinking water and other environmental interventions should be implemented, and if the delivery of interventions designed to protect young children from exposure to bacterial pathogens should be different for rural versus urban communities.