COVID-19 Burden of Disease Amidst Water, Sanitation, and Hygiene (WASH) Challenges and Preparedness: A Scoping Review

Abstract

Background: COVID-19 is an infectious disease caused by the novel coronavirus (SARS-CoV-2), highly transmissible through liquid droplets, and leading to varying health outcomes. However, the rate of morbidity and mortality is exacerbated in patients with chronic diseases. The WHO continues to monitor viral transmissibility and community variants, with explicit guidelines on the implementation of infection prevention and control (IPC) measures, as well as the importance of adequate hygiene and handwashing behavior. Still, basic WASH services are lacking, mostly in developing many countries, constituting a major public health threat. On the other hand, considering the proven effectiveness of WASH services in controlling the transmission of diarrheal and other waterborne illnesses, mostly developed countries are already using the Wastewater-Based Epidemiology (WBE) approach to track and monitor disease prevalence.

Objectives: This scoping review maps out the evidence assessing countries’ implementation of WASH interventions and the use of WBE monitoring in the COVID-19 pandemic, to reflect on the role of WASH preparedness in pandemics.

Methods: This scoping review follows the methodology outlined by the Joanna Briggs Institute (JBI) and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Scoping Reviews (PRISMA-ScR) guidelines. We employed a comprehensive search strategy to identify international evidence from three databases: Medline (Ovid), CINAHL, and Embase. The search was limited to studies published as of November 2019. We included quantitative and qualitative primary studies discussing COVID-19 health outcomes and assessing countries' implementation of WASH interventions. Titles, abstracts, and full articles were independently screened in duplicate by two reviewers, and based on pre-defined eligibility criteria. Data abstraction and analysis was carried out by one reviewer. The studies were classified into two basic themes of WASH services and interventions, and the use of WBE surveillance tool.

Results: Sixty-five out of screened 15,913 studies met our inclusion criteria. Eighty-nine percent of these studies were published in 2021 and 2022. Seventy-three percent of the WASH studies were cross-sectional, while ninety-six percent of the WBE studies were experimental. Most WASH studies were conducted in LMICs, whereas WBE studies were conducted in HICs. The results of the studies highlighted mostly WASH and WBE challenges during the COVID 19 pandemic. 27.27% of WASH studies focused on water scarcity, and 63.63% addressed the limited access to drinking water, and hygiene facilities and supplies. Additionally, 54.54% of WASH studies addressed sanitation challenges, and 18.18% just focused on the exposure of water sources to contaminants. For WBE studies, 81.48% emphasized the significance of this tool for COVID-19 surveillance. Additionally, 55.55% and 25.93% addressed WBE limitations and challenges, respectively. Only 3.7% proposed means for improving this surveillance tool, and provided evidence of its potential use in detecting enhanced adherence to hand hygiene by communities.

Conclusion and recommendations: This scoping review shows that WASH studies are minimal and primarily published in developing countries that are still lagging behind on WASH infrastructures. This suggests that the preparedness of these countries, in the context of future pandemics and epidemics particularly waterborne, is inadequate and WHO recommendations are still considered aspirational, and are not feasible and context specific. As for the use of WBE surveillance tool, its application favors developed countries with well-established WASH infrastructure. Notably, WBE studies align with WASH study findings reflecting on limited progress towards achieving SG6 WASH targets. Subsequently, morbidity and mortality rates would continue to rise exacerbated by the cumulative effects of climate change. Additionally, the implementation of WBE complements the provision of WASH, and realistically not applicable in humanitarian emergency settings, lacking WASH infrastructures, like those in Lebanon and other developing countries. The identified gaps in WBE information necessitate further research into its application in humanitarian emergency settings, such as the situation in Lebanon. Thus, additional studies are required to document evidence on the impact of WASH interventions and associated burden of disease, particularly for vulnerable populations such as climate migrants and refugees.