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  • Signatures of adaptive decreased virulence of deformed wing virus in an isolated population of wild honeybees ( Apis mellifera )
Title: Signatures of adaptive decreased virulence of deformed wing virus in an isolated population of wild honeybees ( Apis mellifera )
Understanding the ecological and evolutionary processes that drive host–pathogen interactions is critical for combating epidemics and conserving species. TheVarroa destructormite and deformed wing virus (DWV) are two synergistic threats to Western honeybee (Apis mellifera) populations across the globe. Distinct honeybee populations have been found to self-sustain despiteVarroainfestations, including colonies within the Arnot Forest outside Ithaca, NY, USA. We hypothesized that in these bee populations, DWV has been selected to produce an avirulent infection phenotype, allowing for the persistence of both host and disease-causing agents. To investigate this, we assessed the titre of viruses in bees from the Arnot Forest and managed apiaries, and assessed genomic variation and virulence differences between DWV isolates. Across groups, we found viral abundance was similar, but DWV genotypes were distinct. We also found that infections with isolates from the Arnot Forest resulted in higher survival and lower rates of symptomatic deformed wings, compared to analogous isolates from managed colonies, providing preliminary evidence to support the hypothesis of adaptive decreased viral virulence. Overall, this multi-level investigation of virus genotype and phenotype indicates that host ecological context can be a significant driver of viral evolution and host–pathogen interactions in honeybees.  more » « less
Award ID(s):
1645331
PAR ID:
10515233
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
The Royal Society
Date Published:
Journal Name:
Proceedings of the Royal Society B: Biological Sciences
Volume:
290
Issue:
2009
ISSN:
0962-8452
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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