Patterns in Ebola Virus Disease Outbreaks: A Systematic Review of Epidemiological Trends and Contributing Factors

Abstract

Ebola Virus Disease (EVD) is a life-threatening condition caused by Ebola virus. It has case fatality rates ranging from about 25% to 90%. Since its first discovery in 1976, EVD has become a persistent public health challenge, especially in sub-Saharan Africa. In this review, we consolidated data from 1976 to 2024 to examine epidemiological trends, transmission patterns, and factors contributing to EVD outbreaks. We searched PubMed, Springer, PubMed Central, Wiley Online Library, and official reports from the WHO and CDC, and these identified 19 studies meeting the inclusion criteria. Findings showed a progressive increase in outbreak frequency, scale, and geographical spread, with the 2014-2016 West African outbreak marking a turning point in EVD epidemiology. The main transmission pathways that were identified included zoonotic spillover events, humanto-human transmission, healthcare-associated infections, and cultural burial practices. Risk factors such as environmental alterations, socioeconomic inequalities, cultural practices, and weaknesses in the healthcare system exacerbated outbreak severity and persistence. Despite advances in diagnostics and vaccines, challenges persist in predicting, preventing, and containing Ebola outbreaks. This review highlights the need for sustained investment in disease surveillance, medical facilities, public participation, and global partnerships to reduce the impact of future EVD epidemics. Dealing with these challenges through a multidisciplinary approach will help reduce the global burden of EVD.