Bees with resistance to varroa mites

**Mike Cox** · 10-03-2016, 01:48 PM

Originally Posted by fatshark

Eh ... ? If this were the case, Type B should predominate globally. I don't think the ISME J. paper describes taking a type B colony (colonies) and parking them in a region with a 'normal' distribution of Type A and C (and D - Z?), and the varroa that transmit them, and seeing what happens.

One question which I felt was not really addressed in that article was whether the Superposition works the other way. If TypeB protects against TypeA, does TypeA also protect against TypeB? My suspicion is that if the viral load of TypeA was sufficiently high for the protection to work then the colony would already be on the point of collapse.

**SDM** · 10-03-2016, 01:53 PM

Originally Posted by Mike Cox

I'm really not convinced by this argument. Are you proposing that your bees which do not display the most grotesque external signs of DWV are actually totally virus free? I'm fairly certain it has been shown that all bees carry viruses all the time, pretty much as we do. A virally "empty" bee is a niche waiting to be filled - I really don't see how it can be possible.

If you have evidence for claiming that TypeB is more likely to cause mutations I'd like to see that, as I'd also like to see evidence that your bees have NO viruses present.

DWV is one of the fastest evolving groups , any variety is likely to mutate. It most certainly does not exist in all bees. I believe the figure is that it's found in 80% of colonies but absolutely not in all bees within infected colonies.
It has been demonstrated by injecting multiple strains of virus into individual bees that one strain , type B in the case of dwv always wins.

**Jon** · 10-03-2016, 02:21 PM

If anyone posting on the thread has not read the Martin Hawaii paper, 2012 yet, it provides really useful background to all this.

Stephen J. Martin
Global Honey Bee Viral Landscape Altered by a Parasitic Mite

European DWV variants were already present
in honey bee populations before the arrival of
the mites. Studies in the United Kingdom
and New Zealand) have found that DWV
infections and colony collapse did not coincide
with the arrival and establishment of
Varroa ,but
there was with a 1- to 3-year time lag, which we
also observed on Hawaii. This lag appears to be
the time required for the selection of virus var-
iants adapted to mite transmission

DWV exists in bee populations which have never been exposed to mites.
There are several variants of DWV.
After the bee population is exposed to varroa this facilitates the reproduction and dominance of one of the variants which happens to be the variant which is most problematic for honeybees.
If you monitor DWV virus before and then after the arrival of varroa mites, there is a reduction in the number of variants of the virus and the lethal variant will have taken over.
Not sure what mechanism is in play with Ron Hoskins bees.

Fatshark, do you still see that Martin paper as very relevant to all this or have things moved on apace since it was published?

**Mike Cox** · 10-03-2016, 02:27 PM

Originally Posted by Jon

Not sure what mechanism is in play with Ron Hoskins bees.

This paper
http://usir.salford.ac.uk/36907/1/is...SEI%202015.pdf
(posted by someone else earlier) grew out of a collaboration between Ron and the researcher. Ron provided the bees and mite samples used. He is mentioned in the acknowledgements.

**SDM** · 10-03-2016, 02:42 PM

Hardly a collaboration, where else would they get type B from.

**Jon** · 10-03-2016, 03:00 PM

Originally Posted by Mike Cox

This paper
http://usir.salford.ac.uk/36907/1/is...SEI%202015.pdf
(posted by someone else earlier) grew out of a collaboration between Ron and the researcher. Ron provided the bees and mite samples used. He is mentioned in the acknowledgements.

Yes, but the paper itself has a series of 'more work needed' 'mechanism still unclear' type comments in the discussion and that it the bit we are all interested in.

In addition the paper's assertion that Ron Hoskins works with a 'closed population' is clearly wrong. Andrew Abrahams on Colonsay works with a closed population but Ron Hoskins bees are exposed to every drone for miles around including all the NZ Carnica drones which were in the area for a while. Whatever way this works, it's not because Ron Hoskins has a closed population.

**Greengage** · 10-03-2016, 03:07 PM

I read too much and I forget where I read it but did I not read somewhere lately that bees were picking up virus from pollen and pollen was also being transfered from bee to bee in the hive as they did not pack all the pollen they collected in their pollen baskets.
Tell me I did,nt read that two posts back, I think I need a break from all this reading about bees.

**SDM** · 10-03-2016, 03:14 PM

Originally Posted by Greengage

I read too much and I forget where I read it but did I not read somewhere lately that bees were picking up virus from pollen and pollen was also being transfered from bee to bee in the hive as they did not pack all the pollen they collected in their pollen baskets.
Tell me I did,nt read that two posts back, I think I need a break from all this reading about bees.

DWV has been found in pollen