Scientists discovered evidence of 27 new viruses in bees

The finding could help scientists design strategies to prevent the spread of viral pathogens among these important pollinators.

The scientists developed a novel high-throughput sequencing technique that efficiently detected in bees both previously identified and 27 never-seen-before viruses belonging to at least six new families in a single experiment. Image: Jeff Kerby / National Geographic
The scientists developed a novel high-throughput sequencing technique that efficiently detected in bees both previously identified and 27 never-seen-before viruses belonging to at least six new families in a single experiment. Image: Jeff Kerby / National Geographic

Populations of bees around the world are declining. According to scientists, viruses are the fundamental cause behind this. Now, a team of scientists at the Penn State has discovered evidence of 27 previously unknown viruses in bees.

In order to investigate viruses in bees, scientists collected samples of DNA and RNA, from 12 bee species in nine countries across the world. They later developed a novel high-throughput sequencing technique that efficiently detected both previously identified and 27 never-seen-before viruses belonging to at least six new families in a single experiment.

David Galbraith, a research scientist at Bristol Myers Squibb and a recent Penn State graduate said, “Despite the importance of bees as pollinators of flowering plants in agricultural and natural landscapes and the importance of viruses to bee health, our understanding of bee viruses is surprisingly limited.”

Populations of bees around the world are declining, and viruses are known to contribute to these declines.  Image: Jeff Kerby / National Geographic
Populations of bees around the world are declining, and viruses are known to contribute to these declines.
Image: Jeff Kerby / National Geographic

Zachary Fuller, postdoctoral fellow at Columbia University said, “Typically, researchers would have to develop labor-intensive molecular assays to test for the presence of specific viruses. With our method, they can sequence all the viruses present in a sample without having any prior knowledge about what might be there.”

“Because the cost of high-throughput sequencing continues to decrease, the team’s approach provides an inexpensive and efficient technique for other researchers to identify additional unknown viruses in bee populations around the world.”

“Although our study nearly doubles the number of described bee-associated viruses, there are undoubtedly many more viruses yet to be uncovered, both in well-studied regions and in understudied countries.”

Christina Grozinger, distinguished professor of entomology and director of the Center for Pollinator Research at Penn State said, “It is possible that bees may acquire viruses from plants, and could then spread these viruses to other plants, posing a risk to agricultural crops.”

“We need to do more experiments to see if the viruses are actively infecting the bees — because the viruses could be on the pollen they eat, but not directly infecting the bees — and then determine if they are having negative effects on the bees and crops. Some viruses may not cause symptoms or only cause symptoms if the bees are stressed in other ways.”

“This finding highlights the importance of monitoring bee populations brought into the United States due to the potential for these species to transmit viruses to local pollinator populations. We have identified several novel viruses that can now be used in screening processes to monitor bee health across the world.”

To investigate viruses in bees, the team collected samples of DNA and RNA (single-stranded DNA) from 12 bee species in nine countries across the world. Image: Jeff Kerby / National Geographic
To investigate viruses in bees, the team collected samples of DNA and RNA (single-stranded DNA) from 12 bee species in nine countries across the world.
Image: Jeff Kerby / National Geographic

In addition, scientists discovered that some of the viruses exist in multiple bee species — such as in honey bees and in bumblebees — suggesting that these viruses may freely circulate within different bee populations.

Other authors on the paper include David Galbraith, Allyson Ray, Maryann Frazier, J. Francisco Iturralde Martinez, Harland Patch, Cristina Rosa, Joyce Sakamoto, Scott Stanley, Anthony Vaudo, and Christina Grozinger, Penn State; Zachary Fuller, Columbia University; Axel Brockmann, National Centre for Biological Sciences, India; Mary Gikungu, National Museums of Kenya; Karen Kapheim, Utah State University and Smithsonian Tropical Research Institute, Panama; Jeffrey Kerby, Dartmouth College; Sarah Kocher, Princeton University; Oleksiy Losyev, National University of Life and Environmental Sciences of Ukraine; and Elliud Muli, International Center of Insect Physiology and Ecology, Kenya.

The results appear in the June 11, 2018, issue of Scientific Reports.