Honey bee viruses are highlighted. Poliovirus (PV) is at the bottom. The relative distance traced along the lines that join the individual viruses give an indication of how closely they are related genetically. For example, IAPV, KBV and ABPV are closely related to each other, as are Sacbrood (SBV), DWV and Varroa destructor virus (VaDV). However, these two groups are only distantly related. From Miranda et al., Journal of Invertebrate Pathology 103 (2010) S30–S47.