THURSDAY, 7 JANUARY 2016In 2012, a team lead by Professor Declan C. Schroeder from the University of Plymouth reported that the arrival of ectoparasitic mite, Varroa destructor, in uninfected bee colonies resulted in colony decline and loss of virus diversity in Hawaii. They particularly observed that a highly virulent variant (type A) of deformed wing virus (DFV) replaced potentially harmless types of DFV and other viruses present before the mite invasion. These observations raised the question of whether virus exclusion could play a role in managing and reducing the decline in honey bee populations.
In a new study, Professor Schroeder and his team report on a viral landscape in an UK apiary that has survived Varroa infestation without chemical control. By using a range of molecular and phylogenetic tools, their work indicates that although honey bee colonies are exposed to the virulent DWV type A, as yet the avirulent DWV type B dominates in their Swindon apiary. The authors suggest that a phenomenon known as superinfection exclusion (SIE), or competition among viruses, might provide protection to the Swindon colonies. In the light of these new results, Professor Schroeder and his group suggest that DWV type B could be used as biocontrol, stating “The discovery of a potential SIE mechanism in honey bees gives those wishing to limit or eradicate the sources of honey bee colony decline the possibility of active intervention”. This study present new hopes for bees and many more questions and challenges for bee-virus management.
Written by Anaid Diaz
Image: By Stefan de Konink (Own work) [CC0], via Wikimedia Commons