Viral Evolution and Honey Bee Colony Collapse Disorder

I first wrote about honey bee colony collapse disorder (CCD) in 2009--

Since ~2006, honey bee colonies in the US have been dropping dead overnight. Literally. They call it ‘colony collapse disorder’. While large populations of organisms dying is disturbing, no matter the species, we need honey bees– they help pollinate so many of our crops. I grew up in the banks of the Missouri River, around apple and peach orchards (who always had their own bee hives, and honey) and hell, I eat everything on that list…

What is killing our bees?

People have accused GMOs and wireless internet and pesticides and antibiotics… We didnt have a clue before.

It might be viruses. Maybe.

That general idea was the same in 2010, 2011, and it looks like this will be the same story in 2012:

Global Honey Bee Viral Landscape Altered by a Parasitic Mite

Okay, so we have looked at what is going on in bee colonies that are failing.  Weve looked at what viruses/bacteria/fungi are 'normal' in thriving bee colonies.

This latest paper suggests that it is a virus that is normally found in healthy and collapsing colonies.

...

... But if the virus is in both populations... how can it play a role in CCD?

It could play a role in CCD because viruses are not clones of one another.

Think about it!  Look at me!  What do I study every day?  VIRAL EVOLUTION.  Two people can be infected with 'HIV-1', and one could be dead in a few years, the other live out their natural lifespan.  Part of what leads to differential disease progression is what version of 'HIV-1' they are infected with.

Same thing with honey bees and deformed wing virus (DWV), apparently.

Think of it this way-- 'Normal' honey bee colonies have a lot of different circulating variants of DWV.  Think of those variants as a bag of Skittles.  Lots of flavors, fairly equal distribution.

Viral diversity in collapsing colonies, on the other hand, is like buying a bag of Skittles, and theyre all lime.  All of them.

You would be like "WTF happened to the diversity???"  Thats exactly what these scientists said when they found a bunch of one kind of DWV in CCD.

Apparently (again, we might totally be off on this, we dont know whats going on), there is a mite population that is spreading DWV around.  DWV is normally spread from bee to bee via oral and sexual routes, and like 10% of the population is DMV positive (with not a lot of negative effects).  These mites act like little IV drug users, going around infecting all the bees they feed on-- almost 100% of the bees are infected with DMV in collapsing colonies.

But wait, theres more--  It looks like there is some kind of selective pressure on the virus, something about being transmitted via the mite, that is causing all of the other flavors of virus/Skittles to disappear.  The mites are selecting 'lime' DMV, infecting all the bees with 'lime' DMV, and 'lime' is killing the bees.

Again, maybe.

What is also super interesting in this paper, is that it was done in Hawaii.  Why is that cool?  Cause the islands are isolated from the rest of the world, and isolated from one another.  This means these scientists could *see* the DMV viral diversity go down, in real time, and compare island to island, which helped them figure out a time-lag between the mites being introduced to the population, and initiation of collapse.  Which explains why other groups who had looked for an association between the mites and collapse might not have seen anything-- their timing was off (it takes the mites and virus time to reduce the viral diversity from 'Taste the Rainbow' to 'lime'.

Anyway-- Super cool paper.  But do we *know* what causes colony collapse?  Do we *know* what to do about it yet?  Nope.

More like this

Having spent 30 years chasing mosquitoes and the diseases they carry,,,thoughts about mites vectoring viruses among bees and the silly hat (or wing) tricks they might be playing are not so far fetched...

Malaria researchers keep banging their heads on the wall ("Look! Malaria might have originated in PRIMATES!") No it didn't you idjits. It originated in BUGS!

PLEASE HELP ME. i HAVE GONE TO THE CRANBROOK
MICH EXHIBIT ABOUT BEES AND DO NOT HAVE ANY
MORE INFORMATION ABOUT THE AFRICIAN BEES AND
THE REASON WHY THEY SEEM TO WANT TO DECIMINATE THE SO CALLED "EUROPEAN BEES" BY KILLIN TH E QUEEN BEES AND NOT PRODUCTING HONEY THEMSELVES BY STORING HONEY IN THE COMBES OF THEIR OWN. CAN YOU VERIFY THIS INFORMATION PLEASE?

By CHARLES SMILLIE (not verified) on 08 Jun 2012 #permalink

PLEASE SEE COMMENTABOVE. MUCH APPRECIATED
BECAUSE I CANNOT FIND OUT THE INFORMATION ON THE INTERNET.

By CHARLES SMILLIE (not verified) on 08 Jun 2012 #permalink

Really, Mr. Smillie, you should be asking such questions on sites devoted to bee-keeping (apiculture). This sort of random question is sometimes perceived by others as "shotgun" research. As an added note, typing in all capital letters is frowned up as the equivalent of shouting.

By passing by (not verified) on 08 Jun 2012 #permalink

Charles, most of what I could find in a cursory Google Scholar search for competitive exclusion of Honeybees had to do with direct competition for food sources (as well as some interesting papers on hybrid colonies). I'd suggest directing your question to someone at MAAREC or a university Entomology department's outreach. Abby is a virologist, not an entomologist. (I'm an entomologist, but as my handle might imply, I study lepidoptera, not hymenoptera.)

By Manduca Sexta (not verified) on 09 Jun 2012 #permalink

Except ... CCD has occurred in Australia, but Australia does not have Varroa mite (yet).

Pdiff:

Just because Australia doesn't have the Varroa mite, doesn't mean that there couldn't be some other vector for the virus that is also preferentially spreading one strain over the others.

Woden,
Agreed, although I'm not aware of what that vector would potentially be. And I do agree that Varroa could well be the main vector in NA as well. I'm not really trying to downplay the virus connection to mites nor the mechanism Abbie is suggesting, but CCD is not easy to pin down to one thing. And DWV as "the" culprit in CCD is unlikely. It affects adult bees, giving them stubby wings, legs, etc. They can't fly. CCD is notable in that the hives are found empty with no dead bees in or around the hive. Either the virus is just a secondary symptom of CCD inclined hives or a variant of the virus is causing otherwise healthy bees to fly off and not return (including young nurse bees and queens which do not normally leave the hive).