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American Foul Brood and European Foul Brood Information

16458 Views 34 Replies 20 Participants Last post by  biffertwrf
There would seem to be AFB spreading around the states in a particularly quick fashion, I will post a series of articles to provide information to those who have yet to experience this disease, will try to gather information on exactly how much a problem for 2009 these diseases are.
[edit] American foulbrood (AFB)

Field test for American FoulbroodAmerican Foul Brood (AFB), caused by the spore- forming Paenibacillus larvae ssp. larvae (formerly classified as Bacillus larvae), is the most widespread and destructive of the bee brood diseases. Paenibacillus larvae is a rod-shaped bacterium, which is visible only under a high power microscope. Larvae up to 3 days old become infected by ingesting spores that are present in their food. Young larvae less than 24 hours old are most susceptible to infection. Spores germinate in the gut of the larva and the vegetative form of the bacteria begins to grow, taking its nourishment from the larva. Spores will not germinate in larvae over 3 days old. Infected larvae normally die after their cell is sealed. The vegetative form of the bacterium will die but not before it produces many millions of spores. Each dead larva may contain as many as 100 million spores. This disease only affects the bee larvae but is highly infectious and deadly to bee brood. Infected larvae darken and die. [7][8]

[edit] History
Until 1906 the two foulbrood diseases were not differentiated and the condition was generally referred to as foulbrood. Phillips (1906) used the terms European and American to distinguish the diseases. However the designations did not refer to the geographical distributions but to the areas where they were first investigated scientifically (Shimanuki, 1990). White (1907) demonstrated conclusively that a bacterium that he called Bacillus larvae was the cause of American Foulbrood (AFB) disease by fulfilling Koch's postulates. The geographical origin of AFB is unknown, but it is found almost worldwide (Matheson, 1993,1996)[9]

[edit] Diagnosis
Lab testing is necessary for definitive diagnosis, but a good field test is to touch a dead larva with a toothpick or twig. It will be sticky and "ropey" (drawn out). Foulbrood also has a characteristic odor, and experienced beekeepers with a good sense of smell can often detect the disease upon opening a hive. In the photo at right, some larvae are healthy while others are diseased. Capped cells with decomposing larvae are sunken, as can be seen at lower right. Some caps may be torn, as well. Compare with healthy brood. The most reliable disease diagnosis is done by sending in some possibly affected brood comb to a laboratory specialized in identifying honey bee diseases. [10]

[edit] Disease spread
When cleaning infected cells, bees distribute spores throughout the entire colony. Disease spreads rapidly throughout the hive as the bees, attempting to remove the spore-laden dead larvae, contaminate brood food. Nectar stored in contaminated cells will contain spores and soon the brood chamber becomes filled with contaminated honey. As this honey is moved up into the supers, the entire hive becomes contaminated with spores. When the colony becomes weak from AFB infection, robber bees may enter and take contaminated honey back to their hives thereby spreading the disease to other colonies and apiaries. Beekeepers also may spread disease by moving equipment (frames or supers) from contaminated hives to healthy ones.

American Foul Brood spores are extremely resistant to desiccation and can remain viable for more than 40 years in honey and beekeeping equipment. Therefore honey from an unknown source should never be used as bee feed, and used beekeeping equipment should be assumed contaminated unless known to be otherwise.[11]

[edit] Treatment

hive to be burned completelyAFB spores are present in virtually every hive. Some brood in weakened colonies can become diseased. If the diseased larva dies within the hive, millions of spores are released.

Antibiotics, in non-resistant strains of the pathogen, can prevent the vegetative state of the bacterium forming. Drug treatment to prevent the American foulbrood spores from successfully germinating and proliferating is possible using oxytetracycline hydrochloride (Terramycin).[12] Another drug treatment is tylosin tartrate that was US Food and Drug Administration (FDA) approved in 2005[13].

Chemical treatment is sometimes used prophylactically, but this is a source of considerable controversy because certain strains of the bacterium seem to be rapidly developing resistance. [14] In addition, hives that are contaminated with millions of American foulbrood spores have to be prophylactically treated indefinitely. Once the treatment is suspended the American foulbrood spores germinate successfully again leading to a disease outbreak.

Destrucción por fuego de la coloniaBecause of the persistence of the spores (which can survive up to 40 years), many State Apiary Inspectors require an AFB diseased hive to be burned completely. A less radical method of containing the spread of disease is burning the frames and comb and thoroughly flame scorching the interior of the hive body, bottom board and covers. Dipping the hive parts in hot paraffin wax or a 3% sodium hypochlorite solution (bleach) also renders the AFB spores innocuous. [15]

[edit] European foulbrood (EFB)
Melissococcus plutonius is a bacterium that infests the mid-gut of an infected bee larva. European foulbrood is less deadly to a colony than American foulbrood. Melissococcus plutonius does not form spores, though it can overwinter on comb.

European foulbrood is often considered a "stress" disease - a disease that is dangerous only if the colony is already under stress for other reasons. An otherwise healthy colony can usually survive European foulbrood. An outbreak of the disease may be controlled chemically with oxytetracycline hydrochloride, but honies from treated colonies could have chemical residues from the treatment. The 'Shook Swarm' technique of bee husbandry can also be used to effectively control the disease, the advantage being that chemicals are not used. Prophylactic treatments are not recommended as they lead to resistant bacteria.
Appearance of brood comb Age of dead brood Color of dead brood Consistency of dead brood Odor of dead brood Scale characteristics Infectious agent
Sealed brood. Discolored, sunken, or punctured cappings. Usually older sealed larvae or young pupae. Lying lengthwise in cells. Dull white, becoming light brown, coffee brown to dark brown, or almost black. Soft, becoming sticky to ropy. Slightly to pronounced putrid odor. Lies uniformly flat on lower side of cell. Adheres tightly to cell wall. Fine, threadlike tongue of dead maybe present. Head lies flat. Black in color. American Foulbrood
Unsealed brood. Some sealed brood in advanced cases with discolored, sunken or punctured cappings. Usually young unsealed larvae; occasionally older sealed larvae. Typically in coiled stage. Dull white, becoming yellowish white to brown, dark brown, or almost black. Watery; rarely sticky or ropy. Granular. Slightly to penetrating sour. Usually twisted in cell. Does not adhere to cell wall. Rubbery. Black in color. European Foulbrood

American beekeepers will soon have a new antibiotic with which to protect their colonies from American foulbrood disease, thanks to Agricultural Research Service (ARS) studies that paved the way for the compound's regulatory approval.

TYLAN Soluble (tylosin tartrate), produced by Elanco Animal Health of Greenfield, Ind., was approved for use October 20 by the U.S. Food and Drug Administration, following the agency's review of research data compiled by scientists with the ARS Bee Research Laboratory in Beltsville, Md.

American foulbrood is among the most widespread and devastating diseases of honey bees. Caused by the bacterium Paenibacillus larvae, the disease kills young bee larvae and transforms their remains into dark, shriveled ropes or "scales." These contain billions of spores that are easily spread by nurse bees. Although American foulbrood poses no human danger, severe outbreaks can weaken or kill entire bee colonies, according to Mark Feldlaufer, who leads the ARS Beltsville bee lab.

Before tylosin tartrate, only one other antibiotic, oxytetracycline hydrochloride (Terramycin), was available for use against American foulbrood. However, reliance on this one compound has prompted the emergence of resistant strains of American foulbrood.

Tylosin tartrate is already approved for therapeutic use in chickens and swine, and as a feed-efficiency aid in turkeys. Its approval for honey bees marks a first for a so-called minor animal species. Feldlaufer's team made this approval possible by furnishing the FDA with a wealth of information on tylosin tartrate's field efficacy and safety, both for honey bees and humans. For example, the team determined the necessary dosage, application methods and timing of treatment in honey bee hives.

Although the drug approval labels honey bees as a "minor animal species," the bee's importance to U.S. agriculture is hardly minor. By one estimate, honey bee pollination of apples, almonds, blueberries and many other agricultural crops results in yield and quality improvements valued at more than $14 billion annually.
This is what I have available for the moment. More will follow please provide me with fed back.
Barry :drinks:


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Here is a site that is worth copying and adding to your bee binder, or keeping a copy in your bee box for in the feild. ... ees_PM.pdf
Barry42001, BjornBee,

Thanks for the info. Both pieces will be placed in my binder when I get home.

Thank you for the information, I'm sure it will be helpful.
additional pictures showing the ropy stretch of dead larvae and the dried down scale in cell of a pupae[attachment=0:1638i4rt]amfoulbrood-2.jpg[/attachment:1638i4rt]


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next pic


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Excellent post Barry!
the pictures are a great help in explaining the appearance of AFB! Thank you for posting.
This is a responce from Bushy Mountians when e-mailed about what they would do if confronted with AFB moderate infection and had other colonies in the area.

" Personally, what I would do in the case of a moderate to severe AFB infection would be to burn. With any case of AFB I would definitely burn all the frames and combs. In a mild case I might try to just scorch/torch the surfaces of the hive bodies and other parts (if they would otherwise have several good years of life left in them), but I don’t think I’d ever want to use even the hive bodies again if the case of AFB had progressed very much at all. If you don’t value your time much, and if the time of year allowed, and if there were very many bees, and if it weren’t a really bad case of AFB, I might try to re-establish the bees as a shook swarm (similar to installing a package.) If I tried to do that at all I would only establish them on old, expendable equipment. I would keep a very close eye on them, and I would burn the whole hive if I saw the least sign of trouble coming back. I would also try to manipulate the way I did things so that the nurse bees would hopefully digest whatever spores they had in their systems before there was any brood ready to be fed in the new hive. As far as other hives and equipment, if I had multiple bee yards I would quarantine the yard that had had the AFB for at least two to three years. In other words, I wouldn’t let any hives or bees or nucs or equipment that had been in the infected yard be used/transferred to clean yards. I would keep an extra close eye on the quarantined yard and start all over again from the beginning if any more AFB showed up. AFB can be highly contagious and spread all over a bee yard, but it’s also quite possible to find a heavily infected hive next to healthy hives and never have those healthy hives develop any AFB. The number one way AFB is spread is probably by beekeepers unwittingly taking frames or supers, etc. from one hive and adding them to another hive. Robbing is probably the second biggest problem to worry about. Of course, if I weren’t confident about what to do I would definitely enlist the help of someone with more experience. Other beekeepers have an extra strong incentive to help when it comes to contagious diseases like AFB. "

Thank you,

Eric Brown
Brushy Mtn. Bee Farm

On Wed, Nov 4, 2009 at 9:41 AM, Barry Cressman <[email protected]> wrote:

Request details:

Name: Barry Cressman
Email Address: [email protected]
Nature of Inquiry : Beekeeping
Question or Comment:
I am a moderator for Beekeeping Forum, and have started a thread on AFB and EFB--there seems to be quite a few members that have AFB not EFB, or atleast none reported as EFB. I have listed a few remedies TM-25, and articles saying the other drug--that I can never remember. Also much discussion about torching the entire colony bees and all. Of course all the possibilities in between. What I want to know to relate to the members--what would you do with a moderate to severe infection of one of your colonies, what would you do with the other colonies in the area. Thank you in advance for any assistance you can offer.
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I haven't gotten a responce from everybody I asked the question of but have one from a respected source:

At the end of the day, burning is the way to go.

Hope this helps.


-----Original Message-----
From: Malcolm T. Sanford [mailto:[email protected]]
Sent: Monday, November 23, 2009 11:56 AM
To: barry cressman
Cc: Ellis,James
Subject: Re: [SPAM] American Foul Brood


There are no good answers to any of your questions about treating for AFB as far as I know, thus the traditional recipe is to burn the colony. This recommendation comes from a long tradition of both research and practical experience. I am copying Dr. Jamie Ellis for his take on the situation.

Malcolm T. Sanford

At 06:18 AM 11/23/2009, you wrote:
>I am currently a moderator in beekeeping forum, and have seen posted
>many requests for advice for control of AFB with advice ranging from
>medicate in place to burn the hive down to the ground--now am aware
>that severity is a factor in deciding treatment
>levels--but were you to discover you had a colony with moderate to
>severe infection of AFB, and you also had several other colonies in the
>immediate area ( as most of us do ), what would you do to the colony
>the infection was noted, and how would you protect the other colonies
>in the area, and how far away from the infected colony
>would you extend your protective measures a 1 mile radius--2
>mile--3 miles radius am seeking as complete a answer as possible I am
>aware that most experienced beekeepers have their opinions as to what
>level of infection demands the more extreme measures to eliminate the
>infection from other colonies in the area.
>Thank you
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What about a gas chamber...cant remeber the typ of gas, but a local beek has a chamber set up to fume old wooden ware.
never seen it mentioned in any of the litrature I have read--nor mentioned by those I have contacted--not saying doesn't exist, but when dealing with something as devastating as this placing your entire bee yard at risk--seems like one has to be as sure as possible to avoid losing your entire apiary descretion better part of valor sometimes anyway.
It's an ethylene oxide chamber, and not all states allow its use
naurot said:
It's an ethylene oxide chamber, and not all states allow its use
North Carolina has one in Raleigh, very inexpensive to use too.
There was a time when ETO Chambers were somewhat popular in many States and the States had them and ran them. Ethylene oxide is a carcenogen and therefore the liability became too much for most States to want to expose themselves to.

Zulu, is the NC chamber still used?
Not Zulu, but Yes, it is still used. I think they charge a buck or buck 50 per box. Quite reasonable.

Sqkcrk, glad to see you back. Haven't seen you in awhile.
Yeah, busy on other Forums and w/ my bees.
Busy with bees is fine, but OTHER FORUMS?? For shame. :shock:
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