EPIWATCH®: A Rapid Epidemic Surveillance Tool for Detecting Early Signals of the First-ever Marburg Virus Outbreak in Equatorial Guinea

Background: On February 13, 2023, Equatorial Guinea identified the Marburg virus for the first time, leading to the declaration of a Marburg virus disease (MVD) outbreak, characterized by a high fatality rate. EPIWATCH® is a rapid surveillance tool that employs artificial intelligence (AI) to detect early signals of outbreaks and the emergence of infectious diseases in real time.Aims: This study aimed to use EPIWATCH® to identify early warning indicators of MVD in Equatorial Guinea during the three months before its official declaration by the World Health Organization (WHO) and local health authorities. Additionally, it sought to examine reported syndromes across regional Africa during the same period to explore potential signals of MVD from the neighboring countries.Methods: We conducted a retrospective analysis using EPIWATCH® to collect syndromic surveillance data from November 2022 to February 2023 in Equatorial Guinea and across Sub-Saharan Africa.Results: There was a notable absence of EPIWATCH® reports regarding Equatorial Guinea in the three months preceding the official declaration of the MVD outbreak, from November 2022 to early February 2023. Additionally, EPIWATCH® reports from neighboring countries did not reveal any syndromic signals of MVD across other regions of Africa during this timeframe. However, a report documenting the syndrome “hemorrhagic fever” in Equatorial Guinea was identified on February 10, 2023, before the diagnosis of the first case on February 12, 2023, serving as the early signal of the 2023 MVD outbreak.Conclusion: The absence of early warning indicators in Equatorial Guinea and across Sub-Saharan Africa in the three months leading up to the official declaration of the outbreak remained unknown. Additional investigations, such as genome analysis or phylogenetic studies, may be required to investigate the outbreak's emergence. AI-based surveillance tools like EPIWATCH® could supplement traditional public health surveillance methods in detecting a wide range of infectious diseases worldwide.