Centre for Water, Sanitation, Health, and Appropriate Technology Development (WASHTED), Malawi University of Business and Applied Sciences, Blantyre, Malawi.
Centre for Water, Sanitation, Health, and Appropriate Technology Development (WASHTED), Malawi University of Business and Applied Sciences, Blantyre, Malawi; Department of Environmental Health, Malawi University of Business and Applied Sciences, Blantyre, Malawi.
Sci Total Environ. 2024 Oct 1;945:174142. doi: 10.1016/j.scitotenv.2024.174142. Epub 2024 Jun 19.
Antimicrobial resistance (AMR) poses a severe global health threat, yet the transmission pathways of AMR within communal public environments, where humans and animals interact, remain poorly explored. This study investigated AMR risk pathways, prevalence, and seasonality of extended-spectrum β-lactamase (ESBL) producing E. coli and K. pneumoniae, and observed practices contributing to environmental contamination within urban, peri-urban, and rural Malawi. Using the SaniPath tool, in August 2020, transect walks across three Malawian study sites identified potential AMR exposure pathways, including drains, standing water, soil, and areas of communal hand contact. Subsequently, from September-2020 to August-2021, 1440 environmental samples were collected at critical points along exposure routes (n = 40/month from each site). These underwent microbiological analysis using chromogenic agar techniques to detect the presence of ESBL E. coli and ESBL K. pneumoniae. Results showed the highest ESBL prevalence in urban environments (68.1 %, 95%CI = 0.64-0.72, p < 0.001) with a higher ESBL presence seen in drains (58.8 %, 95%CI = 055-0.62, p < 0.001) and soil (54.1 %, 95%CI = 0.46-0.62, p < 0.001) compared to other pathways. Environmental contamination was attributed to unavailability and poor condition of sanitation and hygiene infrastructure based on key informant interviews with community leaders (n = 9) and confirmed by independent observation. ESBL prevalence varied between seasons (χ (2,N = 1440) = 10.89, p = 0.004), with the highest in the hot-dry period (55.8 % (n = 201)). Prevalence also increased with increased rainfall (for ESBL E.coli). We highlight that community environments are likely to be a crucial component in AMR transmission, evident in the abundance of ESBL bacteria in identified exposure pathways. Additionally, poor sanitation infrastructure and practices coupled with seasonal dynamics further affect the presence of ESBLs in communal environments. Therefore, a context appropriate whole system approach that tackles infrastructure and behavioural factors, supported by effective surveillance is required to impact AMR and a range of aligned development challenges in these settings.
抗微生物药物耐药性（AMR）对全球健康构成严重威胁，然而，在人类和动物互动的公共社区环境中，AMR 的传播途径仍未得到充分探索。本研究调查了 AMR 风险途径、社区公共环境中广泛存在的产超广谱β-内酰胺酶（ESBL）的大肠杆菌和肺炎克雷伯菌的流行情况和季节性变化，并观察了造成马拉维城市、城乡结合部和农村地区环境污染的行为。本研究于 2020 年 8 月使用 SaniPath 工具，在三个马拉维研究地点进行了横断步行，以确定潜在的 AMR 暴露途径，包括排水沟、死水、土壤和公共手部接触区域。随后，从 2020 年 9 月至 2021 年 8 月，在暴露途径的关键位置采集了 1440 个环境样本（每个地点每月采集 40 个样本）。这些样本使用显色琼脂技术进行微生物分析，以检测 ESBL 大肠杆菌和 ESBL 肺炎克雷伯菌的存在。结果显示，城市环境中的 ESBL 流行率最高（68.1%，95%CI=0.64-0.72，p<0.001），排水沟（58.8%，95%CI=055-0.62，p<0.001）和土壤（54.1%，95%CI=0.46-0.62，p<0.001）中 ESBL 的存在率高于其他途径。基于对社区领导人（n=9）的关键信息访谈和独立观察结果证实，环境卫生和卫生基础设施的可用性差和状况不佳导致了环境的污染。ESBL 的流行率随季节而变化（χ (2,N=1440) = 10.89，p=0.004），在炎热干燥期最高（55.8%（n=201））。降雨量增加时，ESBL 大肠杆菌的流行率也会增加。我们强调，社区环境很可能是 AMR 传播的一个关键组成部分，在确定的暴露途径中发现了大量的 ESBL 细菌。此外，卫生基础设施差和行为因素以及季节性动态变化进一步影响了社区环境中 ESBL 的存在。因此，需要采取一种适宜的、整体系统的方法来解决基础设施和行为因素，并结合有效的监测，以应对这些环境中的 AMR 和一系列相关的发展挑战。
