Insecticides and the mass death of bees

Researchers have identified an Australian virus as a possible factor in the death of bees. Bees are essential in fruit growing industries to pollenate almonds, apples blue berries and lemons. They are worth $US14 billion to US agriculture.

The honey which is produced by the bees in the American plantations is so heavily contaminated with pesticides that it is treated as a waste product and is not consumable.

Could it be that the death of the bees has something to do with collecting all those toxic substances? Might the toxins make them susceptible to illness, such as viruses? Would the bees be better able to resist illness if they didn't have to carry around so much poison instead of pure pollen and concentrate it in the honeycomb in their hives?