Language selection


Viruses in unexpected places: new transmission routes of European honey bee (Apis mellifera) viruses

Colwell MJ, Currie RW, Pernal SF (2017) Viruses in unexpected places: new transmission routes of European honey bee (Apis mellifera) viruses. American Bee Research Conference, 12-13 Jan 2017, Galveston, TX, Bee World 93(4): 106-107.


Although there are many insect pollinators, European honey bees (Apis mellifera) are arguably the most economically important and recognizable pollinators. However, higher than normal losses in the past decade have put the honey bee industry at risk. Viruses are one of the key factors in honey bee health. Little work has been done to explore the possible role of wax, the substrate on which all hive activities take place, as an element in virus transmission. Additionally, no work has been done on the possibility of the inquiline Braula coeca (Diptera) as a carrier of honey bee viruses. This study explores various routes of transmission of viruses between honey bees and wax, and the presence of viruses in Braula compared to Varroa destructor. Potential transmission routes, contact and airborne, were tested in a cage experiment. Bees used in cages originated from two sources, high Varroa (high virus, n=8) and low Varroa (low virus, n=8) colonies. There were also cages with no bees (no virus, n=8), and also two types of wax (light and dark) that were not exposed to the incubator. Bees were taken from six colonies per treatment, mixed together separately, and bee cages each contained 300 bees. All cages contained a sheet of wax foundation. Cages were maintained at 75% RH and 30°C in an incubator for seven days. Both Braula and Varroa were collected with sticky boards from colonies with high Varroa levels. Wax and organisms were tested for viruses (Black Queen Cell Virus and Israeli Acute Paralysis Virus) using quantitative PCR. Viruses were found to be introduced to wax by worker bee contact and by aerosolization within the incubator. Viruses were found in Braula at lower levels than in Varroa. This provides evidence for the possibility of wax as a transmission route, as well as the possibility of airborne transmission of viruses. Additionally, Braula carry viruses, and may serve as vectors within honey bee colonies. Further work is underway to determine if waxborne and airborne viruses are infective to honey bees.

Report a problem on this page
Please select all that apply:
Date modified: