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Chronic bee paralysis virus

Honey bees that appear black, hairless, and shiny may be infected with Chronic Bee Paralysis Virus (CBPV). The symptoms of this virus appear only in adult bees and include the loss of body hair, trembling, and the inability to fly.

Affected bees are often described as “greasy” in appearance and are frequently seen near the hive entrance or clinging to blades of grass in the immediate vicinity of the hive. Their paralyzed wings are often held at an unusual angle that resembles the letter “K.”

Because the healthy workers in a colony will quickly get rid of the infected bees, Chronic Bee Paralysis Virus rarely takes out a whole colony and is considered only a “minor” honey bee disease. However, if you find large numbers of such bees, the colony can be fortified by supplementing the population with brood from another colony. Usually, an infected hive will recover on its own.

Because some research has shown that susceptibility to the disease may have a genetic component, re-queening a hive may be necessary to prevent future outbreaks.

In my own experience, I have seen these symptoms only twice. Both times I found three or four distinctly greasy-looking bees walking around on the top bars with their wings splayed out. I removed these individuals and never noticed any further evidence of disease.

Don’t panic if you see symptoms of the disease, but stay alert. If the incidence of infected bees seems to increase, consider re-queening. As with most viral diseases, there is no cure for CBPV.

Rusty

Comments

Michael
Reply

I have noticed greasy-looking black bees in some of my hives during the winter. I am highly suspecting CBPV, which is also associated with confinement. They leave dark feces in the hive as if infected with nosema but have repeatedly tested nosema-free. It usually shows up in colonies not treated for mites as the colony is weakening in the winter and the population is dropping. It is gross to open a hive on a warmer winter day and see disoriented very greasy bees moping around unable to cluster, and severe defecation blackening parts of the comb or top bars. The infected colonies rarely make it through the winter. Other hives not treated for mites show no symptoms all winter, but I have had bees to come down with it if I move frames of leftover honey from a dead-out to another hive that is low on food supplies. It seems quite contagious. Does anyone know if the virus can live long-term in honey? I have never noticed the trembling at all, and have never seen it during the summer. I treat the badly stained frames by cutting out the wax, scraping the wooden parts, installing new foundation, and letting them set out in the sunlight. Will a bleach solution kill CBPV? (Some viruses are killed by UV light and dehydration, but I do not know if this is true of CBPV.) I live in West Virginia, US.
Found this link interesting: http://www.ibra.org.uk/articles/Chronic-bee-paralysis-virus-infection-in-honey-bees-Apis-mellifera-L
(Click on the “open access” link for the full text PDF)

Rusty
Reply

Michael,

Interesting article. Like I said in my post, I’ve only seen what looked like CBPV twice and in neither case did I have it tested–so I don’t really know. Both times were in late fall or early winter, and in both cases the greasy bees were away from the cluster, meandering around the top bars. The cluster had probably rejected them.

It was scary looking. At first I wasn’t even sure they were bees because their appearance was so altered. But I never saw the disease progress as you describe; I just removed those bees and that was the end of it. If I ever see it again, I will send them in for testing.

In answer to your question, I have no clue how to disinfect for the disease, or if the virus can live outside the host.

Michael
Reply

I think my two hives have CBPV and have lost almost 90% of both hive populations. What do I need to do. Do I burn the hives? Wait out the process and see if the hive survives? Any advise . This all started 7 days ago

Rusty
Reply

Michael,

I don’t have an answer for you. I’ve never heard of burning hives with CBPV. Usually only a small percentage of the bees show symptoms and it doesn’t kill the colonies. I’ve only ever seen a few bees have it; those bees died but the hive lived on. Seven days isn’t much time for a 90% infection. I’ve heard of really bad infections but they are rare, and I certainly have never seen one. I’ve been told it is one of those diseases that is always around but never becomes much of a problem. I really don’t know more than that. Have you called your local extension agent? Maybe they know of outbreaks in your area and what to do about them.

Michael
Reply

I met with a professor from OSU yesterday and took him samples of the bees along with photos I took he said it sounds and looks like my hives got poisoned. He will be running test for tracheal mites, Cbpv and veromos (sp). I have bee samples being tested for poisons with the state of Oregon agriculture pesticide division. I should know more soon

Rusty
Reply

Michael,

Let me know what you find out. I should have thought of pesticide poisoning because it happened in such a short period of time. Makes sense. Too bad about your bees, though.

Wil
Reply

You mention bees clinging to blades of grass but isn’t it normal to have some bees in the grass that are too old and tatered to fly? For instance, I have 5 hives and a very small back yard, I have to be extra careful walking barefoot in the grass. There is probably one bees per square yard. Yes they have worn wings and some have wings that don’t fold together normally. Is this normal or reason to be concerned?

Rusty
Reply

Wil,

Sure it’s normal to have bees in the grass, but when you can no longer see the grass, that is not normal.

Also, I say in the post, “Affected bees are often described as “greasy” in appearance and are frequently seen near the hive entrance or clinging to blades of grass in the immediate vicinity of the hive. Their paralyzed wings are often held at an unusual angle that resembles the letter “K.”

Many greasy bees holding their wings in a “K” is different than a few tattered old bees with worn wings that otherwise appear normal.

David
Reply

Robbing can also create black, hairless bees due to hair loss during fighting. Keep that in mind.

Rusty
Reply

David,

That is true, but they don’t look the same. Fighting bees look black and hairless, but CBPV bees look like someone coated them with motor oil.

Neman
Reply

How can we treat this disease?

Rusty
Reply

We can’t.

Jitka Adeleke
Reply

Hello Rusty,

Something like the chronic paralysis virus happened in one of my hives. I just went inside it today to see what the damage is and I found out that there is no brood, so I guess the girls are on top of that queenless (maybe the thousands of disoriented bees around the hive are just a sign of queenlessness?). There are still few thousands bees tending to their supplies – a lot of full honey frames, they were still not completely robbed.

My question is – is it still worth it to requeen, we have still at least a month or so of nice weather here in North California. Would they be able to make it, or would she die of the same virus herself as well?

Sorry, this is my first year and first disaster so I am trying to save the day. Thanks, Jitka

Rusty
Reply

Jitka,

Have you looked for the queen or are you just assuming she is gone? Colonies often have very little or no brood this time of year, so I would not jump to conclusions. Remember, the bees are actively lowering the population in preparation for winter, they are not trying to increase it.

Also, you say there are thousands of disoriented bees around you hive. What do you mean? Are they outside doing orientation flights? If so, that is a good thing. Or are they on the ground writing and dying?

And why do you assume chronic bee paralysis? Do you see lots of bees in that condition?

You say this is your first disaster, but what you are describing sounds pretty normal to me. If you could answer these questions, maybe I would get a better picture.

Jitka Adeleke
Reply

Hello Rusty,

Yes I did look for the queen and she was not there. And there was no brood whatsoever, only a few half emerged dying bees. Now the hive is completely dead anyways so that was it.

By disoriented I meant crawling on the ground within 2 yards from the hive, not able to fly, being bullied by a few wasps and eventually dying. I did not see any other specific condition but since it was not sudden – this was slowly happening over the last 3 weeks, number of dead bees on the ground increasing – we ruled out poisoning. So I was looking for other diseases and came across this one that seemed to fit the bill the best. I am planning to send a sample to USDA for testing, just to know what happened.

Thanks for your time and help, Jitka

Rusty
Reply

Jitka,

I still wouldn’t suspect chronic bee paralyses virus, but perhaps tracheal mites, although it seems the wrong season. Let us know what you find out. I would really like to know.

Jitka Adeleke
Reply

Sure, will do. Actually the tracheal mites were my first guess but in some other beekeeping forum they told me that that disease ‘does not exist’ any more in USA so i crossed it out. As I said, I am a first timer and have to rely heavily on what other more experienced people tell me 🙂

Rusty
Reply

Jitka,

Tracheal mites took a dive because of Varroa mite treatments, but some places are reporting a comeback of tracheal mites in the last couple of years. It is believed that some strains have developed resistance to the varroa mite treatments. Although it it probably unlikely to be tracheal mites, I definitely don’t think it’s impossible. Tracheal mites do exist in the USA.

Dan
Reply

I have one hive confirmed CBPV and Lake Sinai Virus 1. Despite these viruses, with its current population and stores, I doubt it would make it through the winter. I had planned to combine with another hive but with these confirmed diagnoses have decided not to. But now I don’t know my options. Try to nurse it through the winter and requeen in the spring? Destroy the bees and current brood comb? There is a deep of fully drawn but empty comb. Can I use it in a nuc next year? I’d hate to lose all the comb as well as the bees.

Rusty
Reply

Dan,

I need to double check on this, but I don’t believe these viruses can survive outside of the host bee, so the drawn comb will be fine. As for the bees, these viruses by themselves usually don’t take down the entire colony. The bees may be able to be nursed through it. You just have to decide whether it’s worth it to you.

Dan
Reply

Thanks Rusty. I might try to get them through the winter. No real good options.

Denise
Reply

I am a new beekeeper in Ohio and I went into my hive today and saw something that I am not sure what it is. I have 3 medium boxes and I use a top feeder. I have been feeding sugar syrup and right in the middle of my 2nd box there is a 3 inch wide section from the top of the frame to the bottom of the frame of what looks like maple syrup and dead black bees attached to the comb. There is no foul smell, but I don’t have any brood and cannot seem to locate my queen. Any thoughts?

Rusty
Reply

Denise,

Nothing occurs to me. That you don’t have any brood is typical for November. And since she’s not laying right now, the queen may just be running around and hard to find. But the strip is weird. Are the dead bees in the syrupy stuff? That could make them look black. How about small hive beetles? Do you have any? Are you sure the comb wasn’t scraped against something? How about the comb opposite the strip? Does it look weird too? Are the cells broken or is the syrup on top of capped cells? Do you have a photo?

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