Viral Mysteries: Colony Collapse Disorder

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:

Iridovirus and Microsporidian Linked to Honey Bee Colony Decline

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.

They are not protozoans. They are fungi. :) Hey, weve also thought some viruses were bacteria before :)

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.

More like this

What the authors likely meant is to refer to the Microsporidian as a Protist as opposed to a Protozoan. Although the exact definition of both of these terms is somewhat iffy. While Microsprodians are clearly highly derived fungi, modern usage of the term protist is meant to mean any unicellular eukaryote that doesn't generally form colonies or if it does form colonies exhibits no tissue differentiation. This includes various fungi and close relatives of fungi and Metazoa. Protozoa is generally reserved for the hetertrophic protists (so excluding algae) and often to also exclude fungal species. Its even trickier in usage than protist.

Neither term is phylogenetically meaningful because both refer to a paraphyletic group of organisms. Certainly those that I know where were involved in much of the research showing that Microsporidia were indeed Fungi still refer to them as protists.

=(

I agree with the conclusion you make; the more I read, the more skeptical I become. Nothing is particularly compelling, as far as I can tell.

Personally, i blame the mercury in the vaccines they give to bees. *solemn nod*

Seems to me that CCD has a synthetic etiology, in that no one factor 'causes' it; it is instead the result of multiple causes acting synergistically or nonadditively. These causes include viral & fungal pathogens, insecticides and climate change, along with others yet to be identified. No one factor is solely responsible for CCD but all or several acting in concert cause colonies to collapse and contribute to the decline of apoidean diversity.

By darwinsdog (not verified) on 08 Oct 2010 #permalink

How long until someone incorporates iridovira into Twilight fanfiction?

Never mind the fanfiction. Maybe we can get some of the annoying fan-girls to infect themselves.

One of many things I don't understand: why wasn't this "So a group of researchers apparently put a bunch of bees in a blender..." done sooner?

I heard a research talk about CCD last spring. The speaker described at least four contributing infectious agents (all previously known), but the underlying cause appears to be just poor hygiene on the part of beekeepers.

Disinfecting empty hive frames and putting newcomers into quarantine wasn't important in the past because opportunities for cross-infection were limited. But now queens are routinely shipped all over the world, and hives are trucked around the country and combined and recombined with hives from other sources, creating ideal conditions for the spread of pathogens.

Obviously, colony collapse disorder, along with the die-offs of bats and frogs, is just another sign of the approaching Rapture! LOL!

Just noticed that the Texas Free Thought Convention was this weekend. Hope your talk went well, Abbie.

Hi really like that paper on Mimivirus. They waited to get the whole story before they ran around saying "new human pathogenic virus!". Lots of different lines of evidence, including infection of a lab technician who works with the pure virus.

Maybe some other labs, researching some other potentially pathogenic newly-discovered viruses, should take notes.

@9: if you're making an accusation of fraud, that could be libellous, and if you're not, the information you posted is irrelevant to virology, so probably a bit OT for this blog.

I am loving the Sparkle Virus, but abbie's right, the causation doesn't seem clear. One does have the image of pathologists looking for a cause of Human Being Collapse Disorder- you'd see an awful lot of rhinoviruses and E. coli but that wouldn't mean that colds and gut flora are responsible for people dying.

When the link between IAPV and CCD came out, I was TOTALLY CONVINCED that IAPV wuz killen allz teh beez!!1!!1! Then, I followed the literature for awhile and a bunch of things WUZ KILLEN TEH BEEZ! Then, I started searching for grad schools and forgot about it.

Insect pathology has been an active field for quite awhile, but as I understand things we really didn't start caring about bee pathogens until they started to die. So right now, we're in a stage where we're all like 'HOLY SHIT, BEES GET SICK AND DIE TOO WHARGARBGLE!!!!' and we're seeing all these crazy correlations but don't know fuck about what's actually causing the collapses because we're still not exactly sure what all makes them sick.

Let's take Nosema, for example. Nosema is common among beekeepers, usually at low levels. Place I worked had it, and most other places in the state had it as well. We treated our colonies a couple times a year, but it was continually present as evidenced by the insect shit-stains just outside the colony. I'm not at all surprised it would take hold in a colony weakened by another pathogen. I'm also not at all surprised a colony would die when coupled with something else which was potentially pathogenic.

Could it be a Nosema/Iridiovirus combo? Sure. Could it be IAPV? Maybe. They also could have decided to be those welfare queens Fox news talks about but nobody ever seems to see IRL.

If an entomologically curious gunman put a gun to my head and asked what I thought, I'd tell them that there would probably be more than one factor/disease here and that regional variation in susceptibility could potentially play a role in who gets sick with what. It's the safest thing to say at this point, but nowhere near a 'if we kill this, the bees all come back!!!!' sort of answer everybody wants to hear.

@11: bite me. It's relevant as hell. Perhaps in your little deconstructed world you can separate the bad science from the bad scientists. The adults here can't.

"The long list of possible suspects has included pests, viruses, fungi, and
also pesticides, particularly so-called neonicotinoids, a class of
neurotoxins that kills insects by attacking their nervous systems. For
years, their leading manufacturer, Bayer Crop Science, a subsidiary of the
German pharmaceutical giant Bayer AG, has tangled with regulators and fended
off lawsuits from angry beekeepers who allege that the pesticides have
disoriented and ultimately killed their bees. The company has countered
that, when used correctly, the pesticides pose little risk.

The Bayer pesticides, however, go unmentioned.

What the Times article did not explore -- nor did the study disclose -- was
the relationship between the study's lead author, Montana bee researcher Dr.
Jerry Bromenshenk, and Bayer Crop Science. In recent years Bromenshenk has
received a significant research grant from Bayer to study bee pollination.
Indeed, before receiving the Bayer funding, Bromenshenk was lined up on the
opposite side: He had signed on to serve as an expert witness for beekeepers
who brought a class-action lawsuit against Bayer in 2003. He then dropped
out and received the grant.
"

http://www.commondreams.org/headline/2010/10/10-1

By HurpyDurpy (not verified) on 14 Oct 2010 #permalink

While it may be satisfying to blame those evil pesticides for killing the bees there are laws which must be followed when applying those pesticides.

One of those laws requires farmers to notify all beekeepers who keep bees within a certain radius (~2 miles IIRC), or at least seal them in the hive (which is pretty simple...a wooden stick in the right place will do fine)when they spray. I'm pretty sure there are pesticides and formulations which can't be used around pollination season, either. Not 100% sure on that, though.

There are also pesticides other than neonicotinoids which can affect bees...some forumulations of carbamate pesticides, for example, make the bees think HURR DURR DIS POLLEN PWETTY which ends up with them bringing it back to their nest and feeding the pesticide to their larvae.

So...yeah. There's a possibility newer pesticides are involved because we're not entirely sure how sublethal doses affect bees. One potential conflict of interest (not gonna bother to look at your link, sorry) doesn't exactly prove a nationwide conspiracy especially when there are far less nefarious explanations on the table.

Bees concentrate nectar to make honey.
"Harmless" pesticide residues in the nectar are less than likely to remain "harmless" while they do that.

By Louise E. Rothstein (not verified) on 19 Oct 2010 #permalink

Well, no because it's not as simple as pesticide->bee->honey.

First and foremost as I understand honey production, most of the hives which are used to pollinate crops aren't used to make honey. A lot of the hives used to make honey are set aside for the bees to forage separately.

Another issue is the question of where the nectar comes from. Nectar is stored in a place that's relatively inaccessable...basically inside the flower. Plus, the bee actually ingests the honey so if there were an appreciable concentration of pesticide, I'm sure the bee would die.

The USDA keeps tabs on pesticides in honey, and the only pesticide which shows up in appreciable amounts on a regular basis is Dicofol. These 'appreciable amounts' are under 100 parts per billion, and the maximum acceptable dosage in drinking water is something like 1 part in 10,000.

Soooo...yeah. Pesticide residues in honey are really nothing to worry about unless some jackass lets his bees forage on oleander.

http://www.ams.usda.gov/AMSv1.0/getfile?dDocName=STELPRDC5081750