New research sheds light on deformed wing virus, a threat to honey bees

VIENNA, Nov. 11 (UPI) -- Bees face a multitude of environmental threats. A group of scientists in Austria think one of them is underappreciated and under-studied.

Researchers suggest the presence and rate of infection of deformed wing virus, transmitted to honey bees by parasitic Varroa mites, is the largest determining factor in the survival of bee colonies.

But previous attempts to study the virus have relied on natural samples collected from infected bees.

"Mixed and multiple infections can bias the results of such tests," Benjamin Lamp, a researcher at the University of Veterinary Medicine, Vienna, explained in a news release.

To solve this problem, Lamp and his colleagues built deformed wing virus samples from the group using synthetic genetic material.

"Initially, we amplify the genetic RNA material of a virus and save it as a DNA copy in a vector, a specific transport vehicle for genetic material," Lamp said. "The resulting molecular clone enables us to produce artificial viruses, which are identical and genetically defined."

Their synthetic virus yielded the expected symptoms in exposed bees -- discoloration, dwarfism, death and deformed wings. More than just confirm the effects of deformed wing virus, the new research will allow scientists to more accurately observe and analyze the viral life cycle.

Scientists will also be able to track how the virus is transmitted. Initial tests suggest the virus may be orally transmitted from bee to bee.

By creating an isolated synthetic version of the virus, researchers will now be able to understand how multiple viral infections interact with each other.

"In many cases, a bee is not only infected with one virus species," Lamp said. "Our test system provides a tool to find out, which viruses are especially harmful and how viruses behave in multiple infections. Thus, we can develop targeted strategies against disease-causing viruses."

The new research was detailed in the journal PLOS ONE.

Though scientists participating in the latest study suggest the threat of the deformed wing virus supersedes the impact of pesticides on bee colony health, a number of studies show pesticides reduce the ability of bees to fight off harmful infections.