Disease dynamics of honeybees with Varroa destructor as parasite and virus vector

Abstract

The worldwide decline in honeybee colonies during the past 50 years has often been linked to the spread of the parasitic mite Varroa destructor and its interaction with certain honeybee viruses carried by Varroa mites. In this article, we propose a honeybee-mite-virus model that incorporates (1) parasitic interactions between honeybees and the Varroa mites; (2) five virus transmission terms between honeybees and mites at different stages of Varroa mites: from honeybees to honeybees, from adult honeybees to phoretic mites, from honeybee brood to reproductive mites, from reproductive mites to honeybee brood, and from honeybees to phoretic mites; and (3) Allee effects in the honeybee population generated by its internal organization such as division of labor. We provide completed local and global analysis for the full system and its subsystems. Our analytical and numerical results allow us have a better understanding of the synergistic effects of parasitism and virus infections on honeybee population dynamics and its persistence. Interesting findings from our work include: (a) Due to Allee effects experienced by the honeybee population, initial conditions are essential for the survival of the colony. (b) Low adult honeybee to brood ratios have destabilizing effects on the system, generate fluctuated dynamics, and potentially lead to a catastrophic event where both honeybees and mites suddenly become extinct. This catastrophic event could be potentially linked to Colony Collapse Disorder (CCD) of honeybee colonies. (c) Virus infections may have stabilizing effects on the system, and could make disease more persistent in the presence of parasitic mites. Our model illustrates how the synergy between the parasitic mites and virus infections consequently generates rich dynamics including multiple attractors where all species can coexist or go extinct depending on initial conditions. Our findings may provide important insights on honeybee diseases and parasites and how to best control them.

How to model honeybee population dynamics: stage structure and seasonality

“…We assume that: A1: The daily egg laying rate of honeybee queen is r with the survival rate of H 2 K+H 2 +αB where the parameter K is the population of adult bee needed for half of the maximum brood survival rate and α represents the regulation effects from brood population B. The term H 2 K+H 2 +αB reflects (1) the cooperative brood care from adult bees that perform nursing and collecting food for brood; and (2) the queen and workers that regulate the actual egg laying/survival rate based on the current available brood population B, which has been supported by the literature work [12,21,29,40].…”

Ketalization of 2‐heptanone to prolong its activity as mite repellant for the protection of honey bees

“…Overwintering mortality of the honey bee populations in the US hovers just over 30% . One of the root causes for this decline is the invasion of parasitic mites ( Varroa destructor ) in the bee hives . Varroa destructor is an obligatory parasite that spends its entire life in the bee hive .…”

“…4 One of the root causes for this decline is the invasion of parasitic mites (Varroa destructor) in the bee hives. 1,[5][6][7] Varroa destructor is an obligatory parasite that spends its entire life in the bee hive. 8,9 It was first reported in Southeast Asia but subsequently has spread rapidly all over Europe, North America, South America, Africa and the Asia Pacific region.…”

Brain metabolomic profiling of eastern honey bee (Apis cerana) infested with the mite Varroa destructor

“…The recent sharp decline in honey bee populations has caused a global crisis as the honey bee supply cannot keep up with the increase in agricultural demands [2]. Possible causes of the declines include exposure to certain pesticides, diseases, parasites, and even environmental deterioration [3].…”

“…Possible causes of the declines include exposure to certain pesticides, diseases, parasites, and even environmental deterioration [3]. Worth mentioning, the parasitic mite, Varroa destructor —originally confined to the eastern honey bee, Apis cerana— has become the most detrimental parasite of the western honey bee, Apis mellifera , and currently is considered as the major threat to apiculture [2]. …”