Location: Bee Research LaboratoryTitle: Promiscious feeding on multiple adult honey bee hosts amplifies the vectorial capacity of Varroa destructor
|LAMAS, ZACHARY - University Of Maryland
|SERHAT, SOLMAZ - University Of Maryland
|RYABOV, EUGENE - Collaborator
|SONENSHINE, DANIEL - Old Dominion University
|HAWHORNE, DAVID - University Of Maryland
Submitted to: PLoS Pathogens
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/12/2022
Publication Date: 1/19/2023
Citation: Lamas, Z., Serhat, S., Ryabov, E.V., Mowery, J.D., Sonenshine, D., Evans, J.D., Hawhorne, D.J. 2023. Promiscious feeding on multiple adult honey bee hosts amplifies the vectorial capacity of Varroa destructor. PLoS Pathogens. 19(1): e1011061. https://doi.org/10.1371/journal.ppat.1011061.
Interpretive Summary: Varroa mites are the most important parasites of honey bees. This study focused on the dynamics of mite movement from bee to bee and on the rates at which mites acquire and pass along viral infections. Mites were found to be highly mobile, switching bee hosts daily in some cases. This surprising result helps explain the high correlation between mite numbers and viral infection. Suggestions are raised for controlling the numbers of mites and the movement among bees. Honey bees are the primary pollinators of crop plants and it is vital to control the impacts of disease in order to sustain viable honey bee populations.
Technical Abstract: Varroa destructor is a cosmopolitan pest and leading cause of colony loss of the European honey bee. Historically described as a competent vector of honey bee viruses, this arthropod vector is cause for the global pandemic of Deformed wing virus, now endemic in honeybee populations. Our work shows viral spread is driven by Varroa actively switching from one adult bee to another as they feed. Assays using fluorescent microspheres were used to show the movement of fluids in both directions between host and vector when Varroa feed. Therefore, Varroa could be in either an infectious or naïve state dependent upon the disease status of their host. We tested this and confirm that the relative risk of a Varroa feeding was dependent on the infectiousness of their previous host. Varroa exhibit heterogeneity in this host switching behavior, with some Varroa switching infrequently while others switch at least daily. As a result, relatively few of the most active Varroa parasitize the majority of bees. This multiple feeding behavior has analogs in vectorial capacity models of other systems, where promiscuous feeding by individual vectors is a leading driver of vectorial capacity. We propose that the honeybee-Varroa relationship offers a unique opportunity to apply principles of vectorial capacity to a social organism, as virus transmission is both vectored and occurs through multiple host-to-host routes common to a crowded society.