Fungal-Viral Combination Eyed in Colony Collapse Disorder

A recent study has homed in on a possible explanation for colony collapse disorder (CCD), a mysterious ailment behind the destruction of honeybee hives worldwide. Jerry J. Bromenshenk, et al., “Iridovirus and Microsporidian Linked to Honey Bee Colony Decline,” PLoS One, October 2010. Researchers apparently found that a combined fungal and viral infection led to 100 percent fatality among bees exhibiting CCD, which disorients and disperses hive members. Although previous studies had evidently suspected small RNA bee viruses or other pathogens, no single factor has been “firmly linked to honey bee losses,” according to the study abstract.

Using mass spectrometry-based proteomics (MSP) “to identify and quantify thousands of proteins from healthy and collapsing bee colonies,” the authors concluded that “co-infection” by invertebrate iridescent virus (IIV) and the microsporidia Nosema ceranae is “a probable cause of bee losses in the USA, Europe, and Asia.” Nevertheless, they also stressed the need for further efforts to determine, in part, whether the IIV/Nosema association “is the cause or marker of CCD.” They have suggested that beekeepers facing CCD might be able to disrupt the co infection by “using treatments that are available to control Nosema species.”

Meanwhile, an October 6, 2010, New York Times article has attributed the breakthrough to a unique collaboration between academic and military scientists. Led by University of Montana Professor Jerry Bromenshenk and his “Bee Alert” team, experts reportedly worked with the U.S. Army’s Chemical Biological Center, using sensitive equipment designed to analyze and identify unknown protein combinations. As one microbiologist told the Times, “Our mission is to have detection capability to protect people in the field from anything biological. We brought it to to bear on this bee question, which is how we field-tested it.”