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The Spatio-Temporal Ecology of Oropouche Virus: A Laboratory-Based Modelling Study Across Latin America
Background: Latin America experienced an Oropouche virus (OROV) outbreak of unprecedented magnitude and spread during 2023-24 for unknown reasons.Methods: We tested >9,000 human sera collected between 2001-2022 in Bolivia, Brazil, Colombia, Costa Rica, Ecuador, and Peru for OROV-specific antibodies by serological methods, conducted antigenic and evolutionary characterizations and calculated spatial models using socio-ecological predictors informed by OROV serology and incidence in a machine-learning framework.Findings: Averaged OROV IgG antibody detection rate was 6·1% (95% CI, 5·5-6·6) with substantial regional heterogeneity. OROV infection risk areas predicted by serology-based modelling were significantly correlated with 2024 state-level incidence rates in Latin America and the Caribbean (p<0·001). The predictive power of the serology-based model outperformed an incidence-based model (AUC, 0·78 vs 0·66) and predicted OROV transmission risk hot spots in the Amazon, coastal Brazil, parts of Central America, and the Caribbean, consistent with the 2023-24 outbreak. Longitudinal diagnostic testing of febrile patients suggested constant circulation of OROV in endemic regions at varying intensity. Climate variables accounted for >60% of variable contribution in both serology-based and incidence-based models. Antigenic cartography, evolutionary analyses, and in-vitro growth comparisons showed clear differentiation between OROV and its glycoprotein reassortants, but not between OROV strains.Interpretation: Our data suggest that climate factors are major drivers of OROV spread, potentially exacerbated during 2024 by extreme weather events. OROV glycoprotein reassortants, but not individual OROV strains, likely present distinct antigenicity. Preparedness for OROV requires enhanced diagnostics, surveillance, and vector control in current and future endemic areas.Funding: European Union and others.
Fischer, Carlo and Frühauf, Anna and Inchauste, Lucia and Anzolini Cassiano, Murilo Henrique and Arévalo Ramirez, Heriberto and Barthélémy, Karine and Bautista Machicado, Lisette and Bozza, Fernando A. and Brites, Carlos and Cabada, Miguel Mauricio and Cabezas Sánchez, César Augusto and Cervantes Rodríguez, Angie and de Lamballerie, Xavier and de los Milagros Peralta Delgado, Roxana and de Oliveira-Filho, Edmilson F. and Domenech de Cellès, Matthieu and Franco-Muñoz, Carlos and García Mendoza, María Paquita and Gatty Nogueira, Miladi and Gelvez, Margarita and Gonzalez Gonzalez, Manuel and Gotuzzo, Eduardo and Kramer-Schadt, Stephanie and Kuivanen, Suvi and Laiton-Donato, Katherine and Lozano-Parra, Anyela and Málaga-Trillo, Edward and Manos Alva, Dora Valencia and Missé, Dorothée and Moreira-Soto, Andres and Souza, Thiago and Mozo, Karen and Netto, Eduardo and Olk, Nadine and Pachamora Diaz, Johanna Maribel and Pedroso Jorge, Célia and Pérez Astudillo, Ana Micsuco and Piche-Ovares, Marta and Priet, Stéphane and Rincón-Orozco, Bladimiro and Romero Zúñiga, Juan and Salgado Cisneros, Silvia Paola and Stöcker, Andreas and Villalobos Ugalde, Juan Carlos and Villar Centeno, Luis Angel and Wenzler-Meya, Moritz and Zevallos, Juan Carlos and Drexler, Jan Felix, The Spatio-Temporal Ecology of Oropouche Virus: A Laboratory-Based Modelling Study Across Latin America. Available at SSRN: https://ssrn.com/abstract=5050336 or http://dx.doi.org/10.2139/ssrn.5050336
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