Bacteriophages to combat AFB?

[Bumble]

I've just read this article http://www.dailymail.co.uk/sciencetech/article-2161481/Scientists-turn-viruses-quest-cure-disease-killing-bee-populations.html

Here's a snippet.

Researchers in the U.S. are looking into bacteriophages, viruses that infect and kill specific bacteria, to target the germs behind American Foulbrood Disease (AFD).

I didn't know we'd re-labelled AFB as AFD, but the rest of it looks interesting.

Does anybody have any more details?

Oh, and just a thought. The Mail, true to form, shows pictures of Bumblebees. Do they succumb to the foulbroods?

[fatshark]

There's some very old and incomplete information here (http://www.mendeley.com/research/ppl1c-virulent-mutant-bacteriophage-useful-identification-paenibacillus-larvae-subspecies-larvae/#) which includes the first page of a manuscript published in 1999. Of note is the fact that four of the 137 strains of AFB tested were naturally resistant to the bacteriophage. So, assuming all Paenibacillus larvae strains are equally capable of causing AFB, there's a chance any phage-based therapy might select for these resistant strains.

Gavin will be along in a minute with chapter and verse ;-)

[gavin]

Of note is the fact that four of the 137 strains of AFB tested were naturally resistant to the bacteriophage.

It's the pesticides, I tell you, the pesticides wot did it! Can't be anything else and don't you dare suggest otherwise. I don't care if it was long before neonics were commercialised, must 'uve been the other pesticides then.

I know when I'm out-gunned, so I have nothing sensible to add on phages!

[Neils]

There's some very old and incomplete information here (http://www.mendeley.com/research/ppl1c-virulent-mutant-bacteriophage-useful-identification-paenibacillus-larvae-subspecies-larvae/#) which includes the first page of a manuscript published in 1999. Of note is the fact that four of the 137 strains of AFB tested were naturally resistant to the bacteriophage. So, assuming all Paenibacillus larvae strains are equally capable of causing AFB, there's a chance any phage-based therapy might select for these resistant strains.

Gavin will be along in a minute with chapter and verse ;-)

Isn't that a bit of an assumption? I'm no -ologist, but is it reasonable to assume that all strains are equally capable or equally... virulent (I know that's the wrong word to use in association with bacteria, but I don't know what they right one is) when it comes to causing disease?

[fatshark]

"assuming all P. laevis are equally [virulent]" ... was me just covering my, er, self. I don't know whether they are or not. However, the 'phage was isolated from an AFB-causing strain and the paper proposes using the 'phage to type i.e. identify, P. laevis subs. laevis strains ... the very ones that cause AFB. If such phages were used in a widespread manner the expectation would be that strains naturally (or with acquired) resistance to the 'phage would come to predominate. Not that that's a reason not to encourage this type of research. I suspect it would be a lot more acceptable than a chemical treatment, being analogous to the use of nematodes for slug treatment (now I'm out of my depth).

As an aside, bacteriophages were identified in about 1915. In one of the very first papers d'Herelle suggested using them as therapy for bacterial infections ... ~90 years later after the inexorable rise of antibiotic resistance in bacteria there is considerable interest (http://www.nature.com/nbt/journal/v22/n1/full/nbt0104-31.html) again in this area.

[gavin]

I'd say you are an apidologist at least ;)

The default position is probably that not all strains are equally virulent and there may even be bee strain - pathogen strain interaction *.

Could be the same for bacterium-bacteriophage interactions. Damn. I said that I would add nothing sensible.

Anyway, we use pollen traps that look a bit like bacteriophages. Only bigger.

http://upload.wikimedia.org/wikipedia/commons/thumb/4/4a/PhageExterior.svg/300px-PhageExterior.svg.png
* There's me extrapolating from the potato-pathogen world and maybe I shouldn't be doing that.

[Neils]

One of these days there'll be a thread about databases and then you'll be sorry :D On the plus side we talk about Tuples too.

@fatshark, in some respects that sounds analogous to the recent experience with pesticide treatments (see, we got there properly in the end!) against varroa, though I think that's perhaps the blunderbuss end of the scale perhaps in comparison. how likely perhaps that the conclusion is that this kind of approach ends effectively requiring a "flu virus", i.e. you need a different treatment depending on the strain? For that matter if, god forbid, I get AFB in my hives and you get it in yours, are they the "same" AFB? could they be treated with the same bacteriophage?

[fatshark]

Since the 'phage they isolated was lytic against 134/137 strains I suspect the same treatment would work for both ... however the fact that some P. laevis were not susceptible suggests the phage interacts with a non-essential component of the bacteria, allowing the selection of variants resistant to 'phage lysis.

But we could always query the database ...

SELECT * FROM afb_strains WHERE susceptible = 'yes' ORDER BY strain_id;

;)

[gavin]

I have a lot of respect for a man who uses apostrophes so precisely. However, to be able to time the response to *exactly* 24 hours after the question just leave me a little worried ......

[fatshark]

My reply tomorrow night (timed for 9:37pm) will say "Not so much CCD as OCD" ;)