Scientific Research

Honey bee virus threatens nation's food supply, USDA says

(AXcess News) Washington - USDA researchers, in cooperation with scientists at two leading U.S. Universities, have found that the U.S. population of honey bees is threatened by a virus, which if it cannot be contained could severely hamper food production in the United States on crops that require pollination.

The honey bee virus is called Israeli acute paralysis and is responsible for the collapse of entire colonies.

So how serious a problem is Israeli acute paralysis virus (IAPV) that it would have the food industry buzzing about it?  Researchers found an association between colony collapse disorder (CCD) in honey bees and IAPV, though they have been quick to say they're not positive that the honey bee virus is the culprit behind CCD, but all evidence points to Israeli Acute Paralysis Virus.

This is the first report of IAPV in the United States. IAPV was initially identified in honey bee colonies in Israel in 2002, where the honey bees exhibited unusual behavior, such as twitching wings outside the hive and a loss of worker bee populations. IAPV has not yet been formally accepted as a separate species; it is a close relative of Kashmir bee virus, which has been previously found in the United States.

"This does not identify IAPV as the cause of CCD," said USDA entomologist Jeffery S.Pettis, who led the research team for the Agricultural Research Service (ARS). "What we have found is strictly a strong correlation of the appearance of IAPV and CCD together. We have not proven a cause-and-effect connection."

Israeli Acute Paralysis Virus is a dicistrovirus that can be transmitted by the varroa mite, Pettis explained. It was found in 96.1 percent of the CCD-bee samples.

The next step is exposing healthy hives to IAPV and seeing if CCD develops.

CCD became a matter of concern in the winter of 2006-2007 when some beekeepers began reporting losses of 30 to 90 percent of their hives. While colony losses are not unexpected during winter weather, the magnitude of loss suffered by some beekeepers was highly unusual.

The main symptom is finding no or a low number of adult honey bees present with no dead honey bees in the hive. Often there is still honey in the hive and immature bees (brood) are present.

Pollination is a critical element in agriculture, as honey bees pollinate more than 130 crops in the United States and add $15 billion in crop value annually. There were enough honey bees to provide pollination for U.S. agriculture this year, but beekeepers could face a serious problem next year and beyond if CCD becomes more widespread and no treatment is developed.

The USDA reports that while there are native pollinators (honey bees came from the Old World with European colonists), honey bees are more prolific and the easiest to manage for the large scale pollination that U.S. agriculture requires. In California, the almond crop alone uses 1.3 million colonies of bees, approximately one half of all honey bees in the United States, and this need is projected to grow to 1.5 million colonies by 2010.

The number of managed honey bee colonies has dropped from 5 million in the1940s to only 2.5 million today. At the same time, the call for hives to supply pollination service has continued to climb. This means honey bee colonies are trucked farther and more often than ever before.

Honey bee colony health has also been declining since the 1980s with the advent of new pathogens and pests. The spread into the United States of varroa and tracheal mites, in particular, created major new stresses on honey bees.

There are three major possibilities behind the collapse of entire honey bee colonies that are being looked into by researchers.  One of them is pesticides, but no common environmental agents or chemicals stand out as causative, though even fertilizer is now suspect.  But in California, many almond growers have been switching to an environmentally safe liquid fertilizer manufactured by Itronics, Inc. (OTCBB: ITRO), a Reno, Nevada-based recycler of photochemicals.

Itronics' GOLD n'GRO liquid fertilizer is manufactured at the only plant in the US approved by the EPA and is shipped to distributors in California where it's used on a wide variety of vegetable crops, fruits and orchards due to its safer results for the environment and because it's economically better than the more expensive fertilizers manufactured from petrochemicals that are becoming more suspect of being a pollutant to groundwater nationwide, not just because it may be affecting colonies of honey bees.  Itronics says it has not had its products tested on honey bees, so it could not substantiate any value, though the fact that it's economical and environmentally friendly is good enough reason to consider its use, say California growers.

In 2006, ARS and several university, state and industry participants agreed to sample affected colonies at various locations. That sampling revealed a number of disease-causing organisms, with most associated with "stress-related" diseases (Nosema, European foulbrood, viruses, and others), but no specific cause was determined. The magnitude of detected infectious agents in adult bees suggests that honey bees might be exhibiting some type of immunosuppression; however, researchers have yet to see any measurable effects on the honey bee immune system.

The ARS says that American beekeepers will soon have a new antibiotic with which to protect their colonies from American foulbrood disease, though no antibiotic has been developed for Israeli Virus as yet.

TYLAN Soluble (tylosin tartrate), produced by Elanco Animal Health of Greenfield, Ind., was approved for use October 20 by the U.S. Food and Drug Administration.

American foulbrood is among the most widespread and devastating diseases of honey bees. Caused by the bacterium Paenibacillus larvae, the disease kills young bee larvae and transforms their remains into dark, shriveled ropes or "scales." These contain billions of spores that are easily spread by nurse bees. Although American foulbrood poses no human danger, severe outbreaks can weaken or kill entire bee colonies, according to Mark Feldlaufer, who leads the ARS Beltsville bee lab.

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