title: Effect of oral infection with Kashmir bee virus and Israeli acute paralysis virus on bumblebee (Bombus terrestris) reproductive success.
abstract: Israeli acute paralysis virus (IAPV) together with Acute bee paralysis virus (ABPV) and Kashmir bee virus (KBV) constitute a complex of closely related dicistroviruses. They are infamous for their high mortality after injection in honeybees. These viruses have also been reported in non-Apis hymenopteran pollinators such as bumblebees, which got infected with IAPV when placed in the same greenhouse with IAPV infected honeybee hives. Here we orally infected Bombus terrestris workers with different doses of either IAPV or KBV viral particles. The success of the infection was established by analysis of the bumblebees after the impact studies: 50days after infection. Doses of 0.5×10(7) and 1×10(7) virus particles per bee were infectious over this period, for IAPV and KBV respectively, while a dose of 0.5×10(6) IAPV particles per bee was not infectious. The impact of virus infection was studied in micro-colonies consisting of 5 bumblebees, one of which becomes a pseudo-queen which proceeds to lay unfertilized (drone) eggs. The impact parameters studied were: the establishment of a laying pseudo-queen, the timing of egg-laying, the number of drones produced, the weight of these drones and worker mortality. In this setup KBV infection resulted in a significant slower colony startup and offspring production, while only the latter can be reported for IAPV. Neither virus increased worker mortality, at the oral doses used. We recommend further studies on how these viruses transmit between different pollinator species. It is also vital to understand how viral prevalence can affect wild bee populations because disturbance of the natural host-virus association may deteriorate the already critically endangered status of many bumblebee species.
authors.affiliation: Department of Crop Protection, Ghent University, Coupure 653, 9000 Ghent, Belgium. Electronic address: ivan.meeus@ugent.be.
authors.forename: Ivan
authors.initials: I
authors.lastname: Meeus
authors.affiliation: Department of Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
authors.forename: Joachim R
authors.initials: JR
authors.lastname: de Miranda
authors.affiliation: Laboratory of Zoophysiology, Department of Physiology, Faculty of Sciences, Ghent University, Krijgslaan 281 S2, Belgium.
authors.forename: Dirk C
authors.initials: DC
authors.lastname: de Graaf
authors.affiliation: Biobest, Ilse Velden 18, 2260 Westerlo, Belgium.
authors.forename: Felix
authors.initials: F
authors.lastname: Wäckers
authors.affiliation: Department of Crop Protection, Ghent University, Coupure 653, 9000 Ghent, Belgium.
authors.forename: Guy
authors.initials: G
authors.lastname: Smagghe
mesh_terms: D000818:Animals; D001516:Bees / Q000502:physiology / Q000821:virology*; D056629:Dicistroviridae / Q000502:physiology*; D054884:Host-Pathogen Interactions; D007304:Insect Viruses / Q000502:physiology*; D011157:Population Dynamics; D012098:Reproduction
keywords: Bumblebees; Dicistroviridae; Israeli acute paralysis virus; Kashmir bee virus; Multi-host pathogens