Oropouche virus entomovirology and surveillance: where are we and where are we headed?

Oropouche virus (OROV) is a re-emerging Orthobunyavirus responsible for several large-scale outbreaks across the Americas, with recent introductions into Cuba, a previously nonendemic region, and multiple travel-associated cases reported overseas. Genomic mutations and reassortment events have been proposed as mechanisms that increase virulence, vector compatibility, and alter clinical severity. Despite its growing public health significance, OROV remains a neglected pathogen. Knowledge gaps exist, particularly in terms of vector ecology, incrimination of vector species and viral evolution. This review synthesizes current knowledge on OROV transmission dynamics, focusing on entomovirology, vector competence, and the environmental and anthropogenic drivers behind the 2024-2025 outbreak, as climate change, urbanization, and deforestation are reshaping vector habitats and facilitating spillover. Fragmented data and limited surveillance, especially prior to 2024, hinders our understanding of OROV evolution and spread. We emphasize the need to understand vector‒virus interactions and transmission ecology, as well as the need to design integrative surveillance systems that combine genomic, serological, entomological, and ecological data to improve outbreak preparedness and response strategies.