We report the detection of Moku virus in invasive Asian hornets (Vespa velutina nigrithorax) in Belgium. This constitutes an unexpected report of this iflavirus outside Hawaii, USA, where it was recently described in social wasps. Although virulence of Moku virus is unknown, its potential spread raises concern for European honeybee populations.
Keywords: Belgium; Moku virus; Vespa velutina nigrithorax; invasive Asian hornets; viruses.