Understanding how viral pathogens spread among pollinators to stop Colony Collapse Disorder

In recent years, significant populations of American honeybees (Apis mellifera) have fallen victim to numerous environmental factors, such as mites, pesticides, and pathogens. The resulting widespread die-off of honeybees across the globe is now known as Colony Collapse Disorder (CCD). Honeybees pollinate a staggering 80% of all insect-pollinated crops, including blueberries, cranberries, and apples. Given that the market value of these crops totals over $15 billion, the deleterious impact of CCD will directly affect the global food industry as well.

Though the ultimate cause of CCD remains unidentified, studies have shown CCD is widely associated with RNA viruses, including deformed wing virus (DWV) and black queen cell virus (BQCV). These pathogens cause physiological deformities and bee death. Thus, identifying the prevalence and transmission of DWV and BQCV is essential to preventing the further spread of CCD among bee populations. Previous studies have used molecular biology techniques to identify the presence of viruses within A. mellifera populations solely due to transmission from queen-to-offspring or bee-to-bee. However, recent publications indicate that viral transmission is potentially facilitated by another vector.

From our preliminary analyses, we have identified samples positive for DWV and BQCV in bee species other than A. mellifera, including bumblebees and squash bees. Diagnostic analyses were performed to identify the prevalence of DWV and BQCV in addition to sequencing chosen positive samples for further computational phylogenetic analysis. Increased sequence similarities will indicate the existence of expanded virus transmission and the path of transmission.