Disentangling multiple interactions in the hive ecosystem.

The widespread losses of honeybee colonies recorded over the past number of years in the northern hemisphere represent a major concern for the beekeeping industry and, more importantly, may have a severe impact on ecological services and biodiversity. There is now a general consensus about the multifactorial origin of colony losses, but the mechanistic basis of this complex phenomenon still remains largely elusive. In this review, we propose a functional framework for interpreting how different stress agents can interact to adversely affect bee immunity and health. This provides a new background rationale in which to develop an integrated approach to bee protection, as part of a more comprehensive strategy for the conservation of insect pollinators.