How is deformed wing virus primarily spread among honey bees?

Deformed wing virus (DWV) is primarily spread among honey bees through varroa mites. These ectoparasitic mites feed on the bodily fluids of bees and have become a significant vector for the transmission of various viruses, including DWV. When varroa mites infest a honey bee colony, they can acquire and subsequently transmit the virus to other bees during their feeding activities.

The infection can lead to severe deformities, particularly in developing bees, which is why it receives significant attention in beekeeping. Varroa mites are considered one of the most detrimental threats to honeybee health, and their role in spreading DWV is a critical factor in managing bee populations and ensuring hive viability.

Other options, while they involve factors that affect bees, do not play a significant role in the transmission of deformed wing virus. Pollination activities and contaminated nectar are not primary means through which this virus spreads, as the virus requires a specific vector like the varroa mite to be effectively transmitted. Worker bees, while essential in the hive, are not a means of transmission by themselves without the involvement of the mites.