Parasite free refugia reported from Newfoundland, Canada

Cite: http://phys.org/news/2014-07-parasite-free-honey-bees-enable-bee.html
Paper is free download: http://www.plosone.org/article/fetc....1371/journal.pone.0098599&representation=PDF
Nancy Ostiguy (Penn State) and her colleagues found a geographical area in Newfoundland, in which a number of important invasive honey bee parasites, including Varroa destructor and Nosema ceranae, do not exist. The researchers used molecular techniques to test for the presence of viruses and Nosema ceranae in honey bee colonies managed by beekeepers. They used a visual screening method to search for insect parasites, including Varroa destructor. They then assessed the colonies for visual signs of illness and related the illness data with the presence or absence of parasites or viruses.

In the Newfoundland colonies, the researchers found the parasite Nosema apis, the species that has been displaced by Nosema ceranae elsewhere, and the pathogens, black queen cell virus and deformed wing virus.

"Despite the presence of these parasites and pathogens, colony losses in Newfoundland are very low—similar to the mortality rates reported in the United States before the introduction of Varroa destructor," said Ostiguy.

The team found that the Newfoundland bees, which were otherwise healthy, suffered from K-wing, a descriptive condition of the asymmetrical positioning of the wings that previously was not known to be associated with any identifiable pathogen. The researchers found a significant positive association between the presence of black queen cell virus and K-wing.