Viruses Infecting Cuban Honey Bees and Evolution of Deformed-Wing-Virus Variants

Area of Science:

• Apiculture
• Virology
• Insect Pathology

Background:

• Cuba possesses a large, isolated honey bee (Apis mellifera) population due to a long-standing import ban.
• The parasitic mite Varroa destructor, introduced in 1996, is associated with significant honey bee health issues, including Deformed Wing Virus (DWV).
• Previous surveys indicated widespread Varroa and DWV infestation in Cuban honey bee colonies.

Purpose of the Study:

• To conduct a comprehensive virome analysis of Cuban honey bee samples.
• To identify and characterize the viral landscape, particularly focusing on Deformed Wing Virus (DWV) and its variants.
• To compare the DWV evolutionary patterns in Cuba with those in other global regions.

Main Methods:

• Full virome analysis of honey bee samples collected in 2018 and 2021.
• Detection and sequencing of viral RNA.
• Comparative analysis of viral variants and evolutionary patterns.

Main Results:

• Discovery of two variants of Lake Sinai Virus in Cuba.
• Confirmation of the absence of Black Queen Cell Virus, which is typically widespread.
• Detection of both DWV-A and DWV-B master variants, with DWV-B dominance.
• Identification of a DWV-B/A recombinant, indicating complex viral evolution.
• Cuban DWV evolution patterns mirror those in the USA and Europe, but not in Latin America, China, or Japan.

Conclusions:

• Cuban honey bees exhibit a unique DWV evolutionary trajectory, distinct from many other regions.
• The presence of DWV-B and its recombinant form suggests complex viral interactions and evolution within Cuba's isolated bee population.
• Further research is needed to understand the mechanisms driving these divergent evolutionary pathways of DWV.