Chronic bee paralysis virus

[nicholaskeene]

I have a colony which has been diagnosed with a moderately advanced case of CBPV by the local bee inspector.
He suggested removing the floor of the hive and monitoring the effects for 2 to 3 weeks ( and the floor of the hive stand) so there is now a 18 inch drop below the frames. This I have done....30 dead and dying bees under hive on day one.
I noted the positive posts on this forum in April 2022. The only other suggestion besides requeening that I have seen is shaking the bees 50 yards away and see which ones find their way home..... both seem pretty drastic and risky measures. I would welcome any comments or pointers to an evidence base for either method.

 

[Swarm]

Thirty dead bees doesn't sound a lot, there is usually a pile of dead and dying. You can stick with it and nurse them along, some do recover but far more effective is to change the queen with a new, unrelated one.

 

[user 20297]

I have a colony which has been diagnosed with a moderately advanced case of CBPV by the local bee inspector.
He suggested removing the floor of the hive and monitoring the effects for 2 to 3 weeks ( and the floor of the hive stand) so there is now a 18 inch drop below the frames. This I have done....30 dead and dying bees under hive on day one.
I noted the positive posts on this forum in April 2022. The only other suggestion besides requeening that I have seen is shaking the bees 50 yards away and see which ones find their way home..... both seem pretty drastic and risky measures. I would welcome any comments or pointers to an evidence base for either method.

I'm a couple of weeks into dealing with a colony showing signs of a CBPV infection. Guided mainly by @jenkinsbrynmair clear description of that floor removal procedure, I'm trying to keep the colony going and at the moment the bees seem to be fighting it off by slow increments.

 

[blackcloud]

Drastic measures or miserable decline - not a difficult decision really Nicholas.
And given the nbu default remedy of a shook swarm neither is particularly drastic or risky either.
There was a vid on you tube somewhere showing a long trestle placed at the landing board.
The queen is caged, the bees tipped out at the end of the trestle.Queen is put back into box and only the relatively healthy bees can walk back to to her.
I can't remember if new comb was installed in the box - if so this was essentially a shookswarm.
Jbm s bottomless floor/stand device is possibly at the heart of what your inspector has suggested.
As swarm says thirty bees is not much considering the natural replacement rate of a given colony

 

[Erichalfbee]

I have a colony which has been diagnosed with a moderately advanced case of CBPV by the local bee inspector.
He suggested removing the floor of the hive and monitoring the effects for 2 to 3 weeks ( and the floor of the hive stand) so there is now a 18 inch drop below the frames. This I have done....30 dead and dying bees under hive on day one.
I noted the positive posts on this forum in April 2022. The only other suggestion besides requeening that I have seen is shaking the bees 50 yards away and see which ones find their way home..... both seem pretty drastic and risky measures. I would welcome any comments or pointers to an evidence base for either method.

Do not shake out.
Requeen and have the floor out for 3/4 weeks

 

[jenkinsbrynmair]

The only other suggestion besides requeening that I have seen is shaking the bees 50 yards away and see which ones find their way home

I wouldn't shake out and requeening is a good safeguard for recovery

Jbm s bottomless floor/stand device is possibly at the heart of what your inspector has suggested.

Not my invention - it was Keith Morgan (now retired) RBI who used to be the lead on DASH, seems to be gaining momentum and returning a lot of positive results, although a few of the dinosaurs up there are still sticking to the shook swarm mantra.

 

[user 20297]

I've just watched Richard Noel's latest video, where he passes a hive with CBPV and he comments that he's not sure; is it giving the bees space with the intention of reducing contact that gets them through it, or if they do recover, would that happen in any case?

 

[Erichalfbee]

Increasing space certainly eases overcrowding but do bees social distance if they know they are ill?
Removing the floor or the mesh means that sick bees fall out of the hive rather than be dragged out by another bee which is then infected.

 

[user 20297]

Increasing space certainly eases overcrowding but do bees social distance if they know they are ill?
Removing the floor or the mesh means that sick bees fall out of the hive rather than be dragged out by another bee which is then infected.

Hasn't it been said that the most sickly bees tend either to be forced or choose to go to the periphery of the hive? That's a sort of "social distancing".
Removing the floor and giving space obviously have their respective, physical benefits. But the way that bees are in constant contact with each other and are constantly exchanging fluids as a part of their natural behaviour, seems likely to be a factor that largely overrides the gains made by human management.
My limited observation is that the very young bees are behaving as normal. Drones seem to be disproportionately affected and the "flying" bees that drop look pretty knackered anyway.
From the evolutionary perspective of the virus, it doesn't make sense to decimate that part of the population which is essential to the continuing supply of host bees. Viruses have form on this.....sadly, having their most lethal effects on the older and more infirm in a society.

 

[blackcloud]

But the absence of a floor harnesses one of the major symptoms and targets a big percentage of the vectoring bees precisely in this instance-
the sickly bees whose presence in the hive is only enabled by gravity.

It's a bit wide but you could say that mankind's interference has caused the problem simply by keeping them in boxes.
In the hollow tree cliche they would drop to the base below the entrance and not infect the flying bees or gatekeepers.

 

[Amari]

As I've recently posted, but now an update:
All but one of my eight hives in the main apiary developed CBPV in late April/early May - piles of dead and crawling bees, bad smell etc. Trembling on the landing board. I removed the floors on JBM's advice. Dani advised, in addition, change the queens.

These colonies had all gathered 2 full supers of OSR honey so it's a disease of sudden onset.

When the SBI visited two weeks later (20 May) he felt that there were signs of good recovery and advised leaving the floors off another few weeks. I replaced them early June.

I went through these hives four days ago. All colonies had plentiful BIAS, no dead bees, and the bees seem 'normal' except for possible trembling on one landing board.

Conclusion: hopefully the colonies have recovered without requeening (it would have been difficult to find seven new queens!)

Three other beeks within 2 km of my apiary have had affected colonies.

 

[user 20297]

As I've recently posted, but now an update:
All but one of my eight hives in the main apiary developed CBPV in late April/early May - piles of dead and crawling bees, bad smell etc. Trembling on the landing board. I removed the floors on JBM's advice. Dani advised, in addition, change the queens.

These colonies had all gathered 2 full supers of OSR honey so it's a disease of sudden onset.

When the SBI visited two weeks later (20 May) he felt that there were signs of good recovery and advised leaving the floors off another few weeks. I replaced them early June.

I went through these hives four days ago. All colonies had plentiful BIAS, no dead bees, and the bees seem 'normal' except for possible trembling on one landing board.

Conclusion: hopefully the colonies have recovered without requeening (it would have been difficult to find seven new queens!)

Three other beeks within 2 km of my apiary have had affected colonies.

That's good, positive news.

 

[polymath]

Have to be say I think it is MAD to take a floor off. Has no one ever thought about robbing. It would seem far more sensible if you want room for dead bees to fall to put an empty super under the brood to give extra space. But taking away the floor would seem to me to be an invitation for robbing issues.

 

[Ian123]

It’s a means to an end none said there’s not drawbacks, having said that the cluster is the biggest defence to robbing. I’d ensure the lower frames are covered in bees or brood and problems should be minimised. If you look in nature at exposed colonies, it’s the outer comb that’s robbed not resources within the cluster.

 

[Erichalfbee]

I’ve taken mesh out and the bees were not robbed and survived the virus.
I put an empty super under the brood

 

[Erichalfbee]

Have to be say I think it is MAD to take a floor off. Has no one ever thought about robbing. It would seem far more sensible if you want room for dead bees to fall to put an empty super under the brood to give extra space. But taking away the floor would seem to me to be an invitation for robbing issues.

If you do that the bees still pick the dead and dying bees up to haul them out through the entrance

 

[jenkinsbrynmair]

It would seem far more sensible if you want room for dead bees to fall to put an empty super under the brood to give extra space.

But then the floor is still inside the hive and bees, especially housekeeping and undertaker bees will still be in contact with infected dead bees
I think it's more madness to just ignore the problem and carry on leaving them die rather than risk the odd chance of robbing.
If the colony has gone that weak that it can't defend itself from robbing, it's doomed anyway, might as well just give it a dash of petrol.
People who have tried it have said they have not experienced robbing to any great extent.
Without intervention, the colony is probably doomed, so what have you got to lose?

 

[Mint Bee]

As I've recently posted, but now an update:
All but one of my eight hives in the main apiary developed CBPV in late April/early May - piles of dead and crawling bees, bad smell etc. Trembling on the landing board. I removed the floors on JBM's advice. Dani advised, in addition, change the queens.

These colonies had all gathered 2 full supers of OSR honey so it's a disease of sudden onset.

When the SBI visited two weeks later (20 May) he felt that there were signs of good recovery and advised leaving the floors off another few weeks. I replaced them early June.

I went through these hives four days ago. All colonies had plentiful BIAS, no dead bees, and the bees seem 'normal' except for possible trembling on one landing board.

Conclusion: hopefully the colonies have recovered without requeening (it would have been difficult to find seven new queens!)

Three other beeks within 2 km of my apiary have had affected colonies.

The virus is still there at a sub clinical level and whilst you and neighbours have the current queens your hives will all be susceptible to future outbreaks. Normally triggered by colony stress I believe. There have been plenty of queens available for a couple of months now, and UK breed ones should be about now. Replacement is the only sure way to prevent a reoccurring issue

 

[user 20297]

Another advantage(?) of removing the floor is that on a busy day, my CBPV bees can leave and enter from at least two directions. Yesterday there were some bees orienting towards what I consider to be the back of the hive. Of course, to them, it makes no difference, but it means that they will be conditioned to a situation that further reduces congestion.

 

[blackcloud]

I think it's well worth the risk- inaction will inevitably do similar harm.
Plus you can give the floor /stand/landing board a damn good scub while it's out.

Autumn feed is possibly not the best time to do it though.