Virus May Be the Cause of Bee Disappearance Beekeepers across the country have been opening their hives to find that the bees have vanished. A recent study suggests that a newly discovered virus may be to blame. One of the paper's authors discusses the study and what it might take to stop the decline of the honeybee.

Virus May Be the Cause of Bee Disappearance

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Now, there is an ongoing mystery about deaths, deaths of a lot of, a lot of creatures that would - (unintelligible) anything I think on CSI these days. And now, there is a possible break in the strange case of the missing honeybees.

You may recall that across the country, these bees are disappearing from their hives. And the hives are empty. There really are no dead bees and no obvious problem that beekeepers can see. It looks like the bees just leave the hive and never returned. The phenomenon is called colony collapse disorder and it can wipe out 90 percent of a beekeeper's hive.

There have been lots of theories about what's killing the bees - from cell phone radiation, to genetically modified crops, to global warming - but not one of them has really held up the scrutiny. But now, scientists have a clue. They are reporting a virus might be contributing to the bees' demise.

And joining me now to talk about it is my guest, Diana Cox-Foster, who is professor of entomology at Penn State University. Welcome to SCIENCE FRIDAY, Dr. Cox-Foster.

Dr. DIANA COX-FOSTER (Entomology, Penn State University): Thank you for inviting me.

FLATOW: A virus - and this is a - to me, I've read how you discovered this. This is a great forensic science story.

Dr. COX-FOSTER: Certainly.

FLATOW: You compared - you looked through a healthy colony of bees and looked for differences and what's in the healthy colony and what might be in an unhealthy colony.

Dr. COX-FOSTER: Correct. So it basically was a CSI, only with bees here. We would looked at all organisms that were associated both with healthy bees, from colonies known to survive, and bees in those colonies that were beginning to collapse or collapsing with colony collapse disorder.

FLATOW: Mm-hmm. And so you eliminate - you eliminated the things that did not seem logical and as, I guess, what Sherlock Holmes would say whatever was left, that seemed to be the thing.

Dr. COX-FOSTER: That's right. We ask what were the organisms in common. And opposed to what I'd originally thought that we're going to end up with lots and lots of different organisms, we only ended up with one, which seemed to be highly associated with colony collapse disorder and not present with the healthy bees. And that was the virus Israeli acute paralysis virus.

FLATOW: And where do we think that virus came from?

Dr. COX-FOSTER: So here in the United States, we think that it has come from other countries, perhaps through the importation of bee colonies or use of royal jelly imported from other regions. We know that the virus is distributed in several countries around the world - Israel, where it was originally described, hence, given the name Israeli acute paralysis virus. And we've also found it in bees from Australia and in royal jelly from China.

FLATOW: Hmm. But is that not true that in Israel, when the deaths occurred, the bees die in the hive, not missing like what they do here?

Dr. COX-FOSTER: That's correct. Back when it was reported in 2002, 2004, that was the symptoms that they described, where the bees seemed to undergo spasms and became paralyzed and died at the hive.

So we do think that perhaps the virus has changed overtime or mutated, and that very small changes in the virus may account for differences that we see. Or also that the virus is working, or needs additional pathogens or other triggers in order to cause the symptoms we're seeing.

FLATOW: So you're saying it might not be the only factor?

Dr. COX-FOSTER: That's right. We don't think that it, by itself, is the cause of colony collapse disorder. We do think that there's got to be additional factors playing a role here.

FLATOW: Such as…

Dr. COX-FOSTER: Such as, perhaps, a few other pathogens. We have found that there are three other pathogens that appear to be - have affiliation or association with IAPV, but by themselves they are present in healthy colonies and don't appear to be causing problems.

We also think that perhaps chemicals such as pesticides or herbicides or fungicides may be coming in to the colony at sublethal concentrations and weakening the bees. And then, lastly, we think that perhaps nutritional stress plays a role. Most of the beekeepers who had colony collapse disorder reported having a period of - about two, three months before the collapse as where the bees weren't getting enough pollen or nectar.

FLATOW: So they are stressed and then they get hit with this virus and they - that's the end.

Dr. COX-FOSTER: That's our hypothesis right now. We need to test that next to see indeed if it this virus is the actual cause or if it's just a really good marker for colony collapse disorder. Even if it's just a really good marker, it does give us something to look at to try to predict what colonies are susceptible and apt to undergo colony collapse disorder.

FLATOW: And how did you go about testing that?

Dr. COX-FOSTER: So what we're going to do is we're going to set up screen houses in which isolated bee colonies are kept. And these bees will come from areas where we know that they lack the virus - we'll test them beforehand. And then we will give them the virus in combinations with other stressors and see what happens.

And we have no idea at the beginning here what to expect in terms of what we're going to see or how long it's going to take. So it will be an interesting adventure here.

FLATOW: How come we haven't heard it affecting other bees? Does it affect Africanized honeybees or bumblebees or any of these other kinds of bees?

Dr. COX-FOSTER: So we have looked at some of the stock of Africanized bees, bees primarily out of Arizona that when we sampled them, were completely healthy, and we haven't found the virus there. There are some evidence that we have and others have as well that perhaps the Africanized bees have a much more resistant background or genetic strain towards diseases and real mites as a whole, which would be interesting, if that's the case, that maybe we could use them in breeding for a bee that's much more stronger and able to withstand various pressures.

In terms of other bees, that's a big question out there, other bee species. We know that one other virus found in honeybees does infect bumblebees and can cause symptoms. So we need to begin asking is the Israeli acute paralysis virus is found in other bee species as well, and if it could be contributing to a decline in those species in addition?

FLATOW: Wow. Dr. Cox-Foster, I want to thank you for taking time to be with us. Very interesting.

Dr. COX-FOSTER: Well, thank you for having me.

FLATOW: And good luck to you.

Dr. COX-FOSTER: Thanks.

FLATOW: Dianne Cox-Foster is professor of entomology at Penn State University.

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