Morgan Hiebert, University of Manitoba

Morgan Hiebert1*, Jean T. Coulibaly2,3,4,5*, Fateneba Kone2,3,6*, Elise Gork1, Michaella Jaba1, Abigail Erwin1, Hannah L. Wallace1, Karla Fisher7, Anne W. Rimoin8, Jason Kindrachuk1, Isaac Bogoch9. *These authors contributed equally to this work. 1 Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada. 2 Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire. 3 Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire. 4 Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Allschwil, Switzerland. 5 University of Basel, Basel, Switzerland. 6 Institute of Medical Microbiology and Hygiene, Saarland University, Homburg, Germany. 7 Division of Infectious Diseases, Toronto General Hospital, University Health Network, Toronto, Canada. 8 Department of Epidemiology, Jonathan and Karin Fielding School of Public Health, University of California, Los Angeles, California, USA. 9 Department of Medicine, University of Toronto; Divisions of Internal Medicine and Infectious Diseases, University Health Network, Toronto, Ontario, Canada

Fighting & Responding

Background: Mpox virus (monkeypox virus; MPXV) is responsible for an increasing burden of mpox disease across endemic regions in Africa, and a global outbreak in 2022. Although MPXV circulation is endemic in Cote d'Ivoire, only two human mpox cases were reported prior to 2024, likely underestimating the true burden of infection. Serosurveillance is essential to guide resource allocation, anticipate outbreak dynamics, and inform prevention strategies. The objective of this study is to determine the seroprevalence of MPXV infection in rural and urban regions of Cote d'Ivoire. Methods: Dried blood spot (DBS) samples and demographic information were collected from 1,540 individuals through door-to-door sampling in Abidjan and in rural areas of the Azaguie region of Cote d'Ivoire from 2023-2024. Eluted DBS were tested for IgG detection against MPXV antigens (A29, A35, B6, E8, and M1) and Vaccinia virus (VACV) homologues (A27, A33, B5, D8, and L1) using a quantitative multiplexed electrochemiluminescence immunoassay (V-PLEX Orthopoxvirus Panel 1, Meso Scale Discovery). Seropositivity cutoffs for each antigen were calculated using the mean signal plus three standard deviations. Results: Preliminary analyses from 74 DBS samples showed seroreactivity for MPXV and VACV. Seroreactivity between MPXV antigens and between VACV homologues were significantly different (ANOVA, p<0.05) with MPXV M1R and VACV L1R exhibiting the highest seroreactivity. To date, 5.4% (n=4/74) of samples were seropositive for MPXV. Complete results and demographic analyses to follow. Conclusion: These findings will inform estimates of MPXV seroprevalence and improve understanding of mpox epidemiology in Cote d'Ivoire, including identification of potential risk factors for infection.