Improving risk analysis of the environmental drivers of the spillover, emergence/reemergence, and spread of Crimean-Congo haemorrhagic fever virus, Marburg virus, and Middle East respiratory syndrome coronavirus in the East Africa Region

Abstract

Introduction: Emerging and/or reemerging infectious diseases (EIDs) in the East Africa region are associated with climate change induced environmental drivers. There is a need for a comprehensive understanding of these environmental drivers and to adopt an integrated risk analysis (IRA) framework for addressing a combination of the biological, environmental, and socio-economic factors that increases population vulnerabilities to EID risks, to inform biological risk mitigation and cross-sectoral decision-making. The aim of this integrative review was to identify knowledge gaps and contribute to a holistic understanding about the environmental drivers of Crimean-Congo haemorrhagic fever virus (CCHFV), Marburg virus (MARV), and Middle East respiratory syndrome coronavirus (MERS-CoV) infections in the East Africa Region, to improve IRA processes at the environment-animal-human exposure interface Methods: An integrative review search was carried out to identify relevant studies and reports from 2000 to 2024. Searches were conducted in Embase, PubMed, Web of Science, SCOPUS, CAB Direct, and CAB Digital bibliographic databases; and on the Africa CDC, FAO, WHO, WOAH, and UNDRR websites. Included searches corresponded to the three review questions on environmental drivers, risk frameworks/methodological tools, and One Health policy recommendations for risk analysis. Results: Of the total number of studies retrieved from database searches (N = 18075) and website searches (N= 44), 242 studies and reports combined were included in the review with the majority covering the environmental drivers (N = 137), the risk frameworks/methodological tools (N=73), and the policy recommendations (N = 32). We identified ten categories of environmental drivers, four thematic groups of risk frameworks, and three categories of policy recommendations. Conclusion: This integrative review recommends the adoption of specialized risk mapping approaches such as ecological niche modeling for environmental monitoring of EIDs under IRA processes. Findings from the review were used for the conceptualization of an IRA framework for addressing environmentally driven EIDs.