Im sure this isnt news to any of you– Honey Bees are dying.
We dont know why.
I thought we had an answer to this problem, and the answer was a virus— Israeli acute paralysis virus. But although IAPV definitely has an effect on honey bee immunity, apparently it fell through as The Cause of CCD.
We do not have a honey bee parasitome/microme/virome, so we dont totally know which parasites/microbes/viruses are ‘normal’ and which are the trouble makers, out of the countless parasites/microbes/viruses found in honey bee colonies all over the world. So it could be that CCD is some kind of ‘syndrome’ effecting honey bees– one colonys collapse being caused by one thing, another colony by another thing, etc.
But the features of CCD in honey bee colonies were so specific, it was hard to believe that a collapse in Spain was completely different from a collapse in Iowa.
So a group of researchers apparently put a bunch of bees in a blender and got the Army to figure out what the bees were infected with (Army looked for peptides instead of DNA/RNA– apparently its a neat procedure developed to ID biowarfare agents. huh!). They found that collapsed or collapsing colonies were infected with a) a virus, and b) a fungus:
First of all, that virus is cool.
IIV particles are organized into crystalline arrays. Light reflected from such arrays interferes with incident light, resulting in the characteristic iridescent colours that are the most obvious sign of patent infection. Patent disease is lethal in the larval or pupal stages.
Infected insects sparkle. Heh.
The fungus is also neat. I know about Microsporidian because of their effects on AIDS patients. Youll note in the intro in that link:
Microsporidia are small, sporeforming, obligate intracellular protozoan parasites that are found in the intestine, liver, kidney, cornea, brain, nerves, and muscles of a variety of wild and domesticated animals.
Apparently it isnt enough for a colony to be infected with the virus OR the fungus. They have to be infected with both the virus AND the fungus. They did a neat experiment where they infected bees with one or the other or both, and plotted survival. Bees infected with both died faster.
But I wasnt really excited about that experiment, as they needed more controls. What if they infected the bees with a virus that should have nothing to do with CCD AND/OR a fungus that should have nothing to do with CCD? Its not entirely surprising that if you infect an organism with two deadly things instead of one deadly thing they die faster. There were no diseased controls.
And these pathogens… they were kinda everywhere. Collapsed colonies, collapsing colonies, strong colonies…
Im not 100% convinced this mystery has been solved yet.