Modeling Culicoides paraensis distribution and implications for Oropouche virus transmission in Brazil

Oropouche virus (OROV) is mainly transmitted to humans by Culicoides paraensis, a biting midge widely distributed across the Americas. In this study, we modeled the potential distribution of C. paraensis in Brazil using environmental variables and found that temperature-related factors, particularly minimum temperature and annual temperature range, were the strongest predictors of its occurrence. Comparison of the predicted distribution with confirmed autochthonous OROV cases revealed several areas of mismatch, suggesting either underreporting of C. paraensis or the involvement of additional vector species in transmission. These findings highlight the need to integrate C. paraensis into Brazil's arbovirus surveillance systems and to strengthen entomological monitoring with the support of remote sensing, climate data, and ecological research to better anticipate and mitigate future transmission risks.