California scientists said Tuesday they have identified four new viruses in healthy honey bee colonies. The previously unknown viruses were revealed during a 10-month study of a commercial beekeeping operation that included more than 70,000 hives and 20 colonies that were transported across the United States to pollinate crops. The colonies appeared healthy and did not see any of the mass deaths that have eradicated as much as 30 percent of the U.S. population of honey bees since 2006. Understanding the 27 unique honey bee viruses-including four new ones and others possibly involved in colony collapse-and how they circulate in healthy populations could offer scientists a baseline for further study. Honey bee colony declines in recent years have reached 10 to 30 percent in Europe, 30 percent in the United States, and up to 85 percent in Middle East, according to a U.N. report on the issue released earlier this year. Honey bees are critical to global agriculture. They pollinate more than 100 different crops, representing up to $83 billion in crop value worldwide each year and roughly one-third of the human diet. Among the four newly discovered viruses was one that "turned out to be the primary element of the honey bee biome, or community of bacteria and viruses," said the study, identifying it as a strain of the Lake Sinai virus. Hundreds of millions of its viral cells were "found in each bee in otherwise healthy colonies at certain times of the year," said the research. World health experts believe some combination of parasites, viral and bacterial infections, pesticides, and poor nutrition resulting from the impact of human activities on the environment have all played a role in the bees' decline.
