Isolation and purification of honey bee (Apis mellifera) viruses DWV-A and DWV-B, and discovery of high DWV-B levels in Australian hives free of Varroa destructor

On-Demand

Presenting Author(s)

Kira Peters (she/her/hers)

Research Assistant
University of Manitoba
Waterloo, Ontario, Canada

Co-Author(s)

RC

Rob Currie

Professor and Head, Department of Entomology
University of Manitoba
Winnipeg, Manitoba, Canada
ZR

Zoe Rempel

Technician
University of Manitoba
Winnipeg, Manitoba, Canada

Varroa destructor is an ectoparasitic mite of honey bees (Apis mellifera) that causes significant overwintering colony loss and has a greater impact on apiculture than any other honey bee pathogen. Besides reducing the average weight of individuals in the hive due to feeding activities, V. destructor further damages A. mellifera colonies by acting as a vector for various viruses, including deformed wing virus (DWV), a virus commonly associated with the varroa mite. The two main strains of DWV, DWV-A and DWV-B, were isolated from past stored virus samples, reared in pupae, and purified for use in cage inoculation experiments. Pupae from colonies shipped from Australia earlier in the year were inoculated with virus to rear because they were relatively free of mites and virus and would contribute little contamination. When attempting to rear another virus using the same pupae, significant DWV-B contamination was detected, so the Australian colonies were sampled once again for virus. High levels of DWV-B were discovered despite no presence of V. destructor in the colonies, suggesting an alternate form of transmission causing these elevated viral levels.