Culprit in hive deaths across nation may bee a virus

Scientists sifting genetic material from thriving and ailing bee colonies say a virus appears to be a prime suspect — but is unlikely to be the only culprit — in the mass die-offs of honeybees reported last fall and winter.

The honeybee die-offs, in which adult bees typically vanished without returning to hives, were reported by about a fourth of the nation's commercial beekeepers. The losses captured public attention as rumors swirled about causes ranging from climate change to cell-phone signals to genetically modified crops.

Now, one bee disease, called Israeli acute paralysis virus, seems strongly associated with the beekeeping operations that experienced big losses, a large research group has concluded, although members of the team stressed that they had not proved the virus caused the die-offs.

"I hope no one goes away with the idea that we've actually solved the problem," said Jeffrey S. Pettis, an entomologist with the Department of Agriculture and co-director of a national group working on the puzzle, which has been given the name colony collapse disorder.

The project involved an unusual partnership between entomologists and scientists working at the leading edge of human genetic research. It employed the same technology being used to decode Neanderthal DNA and the personal genome of James Watson, the co-discoverer of DNA.

The research was described in Science Express, the online edition of the journal Science. Details are available at eurekalert.org/bees.

Even with the caveats, the possible identification of a virus involved in large bee die-offs "is exceptionally important," said May Berenbaum, who heads the entomology department at the University of Illinois, Urbana-Champaign, and was not involved in the study. "Among other things, figuring out where this one came from will help us prevent future problems."

Berenbaum, who led a 2006 National Academies study of problems with bees and other pollinators, said that finding ways to swiftly home in on novel diseases is ever more important in a globally linked economy. She noted that the first reports of the latest bee die-offs in the United States came in 2004, the same year the country allowed the first imports of honeybees from another country — in this case Australia — since 1922.

The new study found evidence of the virus in some Australian bee samples, although that country has not reported die-offs like those seen in the United States.

"Globalization clearly has had impacts on emerging and re-emerging infectious diseases of humans," said Berenbaum. "Should bees be any different?