1.2. Sample collection

The optimum strategy for collection and transport of bee samples depends partly on what type of sample is collected. Bees, pupae, larvae and eggs can be sampled whole or as field-dissected components, such as heads, thoraxes, abdomens, guts, endophalli, semen, ovaries etc. Many bee viruses are shed in large amounts in the guts, as are many bacterial and protozoan pathogens (Shimanuki, 1997; Fries, 1997). Faeces may therefore be a good marker for the infection status of the whole bee, although care has to be taken to distinguish between passively acquired/passaged microbes and true tissue infections. Faeces also allow bees to be sampled repeatedly, and non-destructively. It may therefore be useful for determining the virus status of queens (Hung, 2000), especially if these are a major source of infection of the worker population (Chen et al., 2005b; Fievet et al., 2006), or for following disease progression in individual bees.

Below are suggestions for the collection of different types of bee samples. In all cases a priori decisions are all needed with respect to the use of chemical stabilizers, collection cards and the temperatures during transport and storage.

1.2.8. Dead bee samples