BeeWeaver’s thoughts… The paper by Bromenshenk et al., recently published in PLoS One, adds to earlier work suggesting that CCD is characterized by bees which are infected with multiple pathogens. The new and controversial result presented by this group is that a virus never before identified in honey bees, the Invertebrate Iridescent Virus (IIV), may be correlated with CCD. They used proteomic and bioinformatic techniques to generate the new findings. The methods description is not very detailed but I’ll describe what the general approach they employed. In summary, they isolated proteins from colonies with and without CCD, digested those proteins into small peptide fragments, ran those peptide fragments through a liquid chromatography/mass spectrometry (LC/MS) pipeline, and then identified the organisms from which the proteins originated by searching a library of microbial proteins for instances of proteins where the precise detected peptide fragments occurred. Questions have been raised about the feasibility of accurately identifying the correct organisms from which the peptide fragments originated using their techniques, and the omission of the most likely confounding source of proteins (the failed to include honey bee proteins) in the library they searched for peptide fragment matches. Nevertheless, it is interesting that co-occurrence of Nosema cerranae with IIV echoes earlier findings from another group which often detected Nosema cerranae and other viruses in the colonies that were afflicted with CCD. It has been established that one may control Nosema cerranae with the same antifungal compound – fumigillin B – that is effective in treating infections of the previoulsy more common Nosema apis, a cousin of Nosema cerranae and the microsporidian parasite that was originally characterized in honey bees many years ago. As a final note, the authors detected IIV in most populations of bees they examined. One notable exception is Australian honey bees, which they found were not infected with IIV. Find the PLoS research article here: http://www.plosone.org/article/info:doi/10.1371/journal.pone.0013181
