Social insect colonies are potentially rather vulnerable to parasites.  The high density and interaction rate of individuals can aid transmission.  The often low genetic diversity of individuals may also facilitate transmission, as well as being an easier target for parasite evolution and carrying the risk of all colony members being susceptible.  In addition, the relatively constant within-colony environment is conducive to parasite survival.  However, social insect taxa differ in many aspects of their biology and these differences seem likely to have important implications for their relative vulnerability to different parasites.  Here I will consider at a broad scale the implications of host and parasite biology for predicting which social insects are likely to be more or less vulnerable to which parasites.  I will then examine an updated dataset of records of host-parasite interactions for social insects to investigate to what extent the data reflect these predictions, while attempting to control for the problem of non-uniform sampling effort.  In spite of the limitations of current information, an examination of the records at even a broad scale reveals a number of interesting patterns that is suggestive of the importance of both host and parasite biology in determining who is most vulnerable to what.