Viruses, bacteria, and fungi appear to have the strongest link with Colony Collapse Disorder found so far, according to a new study published by Agricultural Research Service (ARS) and university scientists.
The study was headed by Pennsylvania State University entomologist Dennis vanEngelsdorp and entomologist Jeff Pettis, geneticist Jay Evans, and virologist Yanping Chen with the ARS Bee Research Laboratory in Beltsville, MD. The scientists looked at more than 200 variables in 91 colonies from 13 apiaries in Florida and California, two states where many beekeepers overwinter their honey bees. The researchers screened for factors such as bacteria, mites, Nosema (protozoan parasites), viruses, nutrition status and 171 crop protectants. Also sampled were adult bees, wax comb, beebread (stored and processed pollen), and brood.
Their findings showed that no single variable was found consistently in only those honey bee colonies that had Colony Collapse Disorder (CCD). CCD is a syndrome denoted by the sudden disappearance of adult honey bees in a colony.This syndrome has been devastating some beekeepers in the U.S. and other places around the world.
According to the research, overall, CCD colonies were co-infected with a greater number of pathogens. About 55% of CCD colonies were infected with three or more viruses, compared to 28% of non-CCD colonies. The researchers also found detectable levels of residues from 50 crop protectants in all of the sampled colonies. There was no association between increased pesticide levels and CCD.
A report that summarizes research progress on CCD can be found at www.ars.usda.gov/is/br/ccd/ccd_progressreport.pdf