2.1. Where and when to sample a colony

Colony heterogeneity in time and space are important aspects to consider when sampling honey bees and brood. For example, the presence and prevalence of pathogens both depend on the age class of bees and brood, physiological status of bees, and/or the presence of brood. Note that pathogens in a colony have their own biology and that their presence and prevalence can also vary over space and time. The relation between a pathogen and particular features of a colony should be taken into account when deciding where and when samples are taken, including the marked seasonality of many pathogen infections.