What are the vector species of the Oropouche virus?

Oropouche fever, caused by the arbovirus Oropouche virus (OROV; Peribunyaviridae: Orthobunyavirus:Orthobunyavirus oropouche), has significantly increased in Brazil, with >25 000 confirmed cases during the 2023-2025 outbreak. Historically endemic to the Amazon region, OROV is now spreading beyond its traditional range. The vectorial dynamics of OROV transmission remain under scrutiny. Although Culicoides paraensis is identified as the primary urban vector, the role of Culex quinquefasciatus and other culicids is still under debate, as laboratory studies indicate limited vector competence. Entomological investigations highlight the challenges of detecting OROV in nature, with low virus isolation rates from biting midges and mosquitoes. Vertical transmission in mosquitoes suggests potential alternative mechanisms for virus maintenance. Recent outbreaks in the Extra-Amazonian areas emphasize the importance of comprehensive vector studies to refine control strategies. This review synthesizes seven decades of research on OROV epidemiology and vector competence, identifying critical knowledge gaps, such as the definitive wild cycle vector, and we suggest a research agenda. Addressing these gaps is pivotal for preventing further geographical spread, reducing fatalities, and mitigating the public health impact of this emerging arbovirus. © 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.