Honey bee colony losses concern beekeepers and agriculturists alike, as Apis mellifera are important crop pollinators. A pair of factors that affect the health of honey bee colonies are the mite, Varroa destructor—which parasitizes honey bee larvae—and the pathogenic deformed wing virus (DWV), which V. destructor can transmit. Scientists have long tried to understand the details of the mite-virus-bee ecology. It was already known that DWV benefitted from its association with the mite, as the parasite helps the virus spread. But it had been less clear whether the mite gained anything from serving as a viral vector. It turns out that mites show more reproductive successes when parasitizing honey bees with active DWV infections, according to a study published today (March 7) in PNAS.
“We provide evidence supporting the occurrence of a mutualistic symbiosis, unrecognized so far, which accounts for the severe impact of this parasite-pathogen association on honeybee health,” ...
