Effects of honey bee queen exposure to deformed wing virus-A on queen and juvenile infection and colony strength metrics

Abstract

Varroa destructor and the pathogens they vector have contributed significantly to high annual honey bee colony losses. Deformed wing virus (DWV) is the most prevalent honey bee virus and has been associated with overwintering colony loss. DWV is capable of infecting honey bees at all life stages and castes via horizontal and vertical transmission. Few studies have been conducted to determine the effect that pathogens have on honey bee queen health and performance. Our results suggest that queens may have mechanisms that reduce the establishment of DWV infection following a single exposure event. A queen’s exposure to DWV-A prior to colony establishment did not significantly negatively impact colony strength metrics for two of three queen genotypes tested. Additionally, brood showed little subsequent infection. These findings suggest that when queens experience a single oral or venereal inoculation of DWV-A, vertical transmission may not result in significant brood infection and that overall colony strength may be largely unaffected. Increased colony loss experienced by colonies derived from one queen source indicates that differences in susceptibility exist due to factors that need to be investigated more fully. These findings contribute to a greater understanding of host-pathogen interactions in honey bees and suggest a context-dependent variability on the influence of queen exposure to viruses on colony health.

Keywords:

• DWV
• Apis mellifera
• vertical virus transmission
• transgenerational effect
• honey bee viruses
• bee pathology

Acknowledgements

We thank Garrett Dodds, Phil Tokarz, Hannah Penn, and Christopher Fellows, for key contributions to the completion of this study. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. U.S. Department of Agriculture is an equal opportunity provider and employer.

Disclosure statement

The authors report there are no competing interests to declare.

Additional information

Funding

This work was supported by funding from United States Department of Agriculture-National Institute of Food & Agriculture Grant 2017-69004-26515 awarded to KH and MSF and the United States Department of Agriculture, Agricultural Research Service Research Plan 6050-21000-014-00D.