Co-occurrence of RNA viruses in Tasmanian-introduced bumble bees (Bombus terrestris) and honey bees (Apis mellifera)

A number of bee RNA viruses, including Deformed wing virus (DWV), are so far unreported from Australia. These viruses can be introduced together with imported live honey bees (Apis mellifera) and their products, with other bee species, and bee parasites. Given that bee viruses have a profound impact on bee health, it is surprising that since the introduction of bumble bees (Bombus terrestris) onto Tasmania in 1992 from New Zealand, no work has been done to investigate which RNA viruses are associated with these bees. Consequently, we investigate the current prevalence of RNA viruses in B. terrestris and A. mellifera collected in south-eastern Tasmania. We did not find DWV in either A. mellifera and B. terrestris. However, both bee species shared Kashmir bee virus (KBV) and Sacbrood virus (SBV), but Black queen cell virus (BQCV) was detected only in A. mellifera. This reinforces the importance of ongoing strong regulation of the anthropogenic movement of live bees and their products.