Bluetongue in ruminants: Global epidemiology, pathogenesis, and advances in diagnostic and control strategies within a One Health framework.

Bluetongue (BT) is an economically important viral disease of domestic and wild ruminants, caused by the bluetongue virus (BTV), and transmitted primarily by Culicoides midges. The virus has at least 28 known serotypes and several emerging strains, with its distribution expanding beyond traditional endemic zones due to climate change and global trade. This review summarizes recent developments in the epidemiology, molecular characterization, diagnostics, vaccines, and control of BT, with an emphasis on its implications within the One Health framework. A comprehensive literature search covering studies from 2000 to 2025 revealed significant outbreaks in Europe (2024-2025) involving BTV-3 and BTV-12, as well as the emergence of novel serotypes in Asia and Africa. Global economic losses exceed USD 3 billion annually due to mortality, production losses, and trade restrictions. Advances in molecular diagnostics, such as reverse transcription polymerase chain reaction, whole-genome sequencing, and rapid field assays like loop-mediated isothermal amplification and clustered regularly interspaced short palindromic repeats -based platforms, have improved surveillance and serotype identification. Although vaccination remains the cornerstone of BT control, current live and inactivated vaccines are limited by serotype specificity and reassortment risks, highlighting the need for new-generation virus-like particle, recombinant, DNA, and mRNA-based vaccines. Persistent challenges include the absence of differentiating infected from vaccinated animals -compatible polyvalent vaccines, incomplete knowledge of wildlife reservoirs, and uneven surveillance capacities worldwide. Strengthening integrated vector management, genomic monitoring, and climate-informed control strategies through a coordinated One Health approach will be vital to reduce the global burden of bluetongue.