Appearance of acute bee paralysis virus, black queen cell virus and deformed wing virus in Carnolian honey bee (Apis mellifera carnica) queen rearing

We studied the appearance of acute bee paralysis virus (ABPV), black queen cell virus (BQCV) and deformed wing virus (DWV) in workers and queens during queen rearing. Different castes (i.e., workers, attendant workers, and queens) and colony materials (i.e., adult tissue and faeces) underwent virus testing. First, newly emerged queens were tested for the three viruses. Second, we tested for these same three viruses in queen faeces, offspring, and attendant workers. These bees were gathered 3, 6 and 9 weeks from mating nuclei after queen cells were introduced. Viruses occurred sporadically during stages of queen development; for instance, queen larvae may test positive for viruses, whereas pupae tested negative, and vice versa. In the first year of the experiment in all samples of workers in mating nucs BQCV was detected, while the prevalence of the same virus in queens was 50%. Next year the prevalence of BQCV in mating nuclei was low, that is, 4.2%, all queen samples were negative for BQCV. Thirteen queen samples (72%) were positive for DWV in the second year of the experiment. Although DWV was detected in queens and queen faeces, workers from the same nucleus were often free of DWV. ABPV appearance in queens was among the rarest of the tested viruses. Our results indicate that these three honey bee viruses are present when rearing queens, yet appear benign to infected bees.