Sulfa drugs were not banned in the US, but their approval for use on hives was not reapplied for, hence they became illegal without this approval. "They were effective against AFB, but their stability and consequent residues in honey caused problems, and the registration was allowed to lapse in the 1970s" ( J. Kochansky et al. 2001)



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Early State efforts certainly reduced AFB incidence, however the widespread use of antibiotics (Sulfathiazole in the 1940s and 1950s, Oxytetracycline from the 1950s until the 1990s, and more recently Tylosin tartrate has significantly (and arguably more dramatically) reduced the incidence of bacterial diseases. However, while prophylactic use of antibiotics may prevent disease outbreak, discontinuation of regular antibiotic application often results in disease reoccurrence. -- A historical review of managed honey bee populations in Europe and the United States and the factors that may affect them. Dennis vanEngelsdorp and Marina Doris Meixner. Journal of Invertebrate Pathology Volume 103, Supplement 1, January 2010



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Sulfathiazole resistance: Sulphonamides suffer from increased bacterial resistance and high toxicity. In the 1990s all the isolates tested in Germany were classified as resistant to this class of drugs. Sulfathiazole lost its FDA approval about 30 years ago. Nevertheless, residue levels in honey from the EU market seem to indicate that the use of this substance is still widespread. Due to the development of resistant strains of AFB and varroa and the problem of residues (antibiotics in honey and acaricides in wax), the limits of chemotherapy have become evident. -- LIMITS OF CHEMOTHERAPY IN BEEKEEPING: DEVELOPMENT OF RESISTANCE AND THE PROBLEM OF RESIDUES by Marco Lodesani. Bee World, 2005



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Many years' experience and research have shown that effective control of AFB without the use of veterinary drugs is possible. Therefore, to avoid residues in bee products and resistance of the pathogen, control measurements without veterinary drugs should be implemented in the management plans for all beekeepers. It is our experience that the same plans may be implemented for hobby, semi-commercial, and commercial beekeepers. For sustainable beekeeping it is very important to educate beekeepers in control strategies for AFB and bee diseases in general, which prevent drug or pesticide residues. Honey bee tolerance should be included in the strategies. Therefore, breeding programmes should include a test for hygienic behaviour on promising bee strains.  -- The spread and control of American foulbrood (BfD Journal 76) By Henrik Hansen and Camilla J Brodsgaard, Denmark



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Before he from USDA Bill Wilson prepared a retrospective on AFB:



An Overview of Foulbrood in the United States: the Past 45 Years



American and European foulbrood (AFB & EFB) are bacterial diseases of honey bees that are highly contagious and spread rapidly between bee colonies and apiaries. Before the mid-1940s, the only reliable means of limiting the spread of AFB (Paenibacillus larvae) was to shake adult bees onto wax foundation or kill the colonies and burn or boil all of the combs and wooden equipment



Discovery in the mid-1940s that sulfa drugs could control European foulbrood (Melissococcus pluton) disease ushered in a new era. Some bee inspectors did not initially accept sulfa treatment as valid, but eventually most beekeepers and inspectors realized the economic value of protecting colonies with this chemical treatment. It wasn't long before the practice became widespread, making large-scale commercial beekeeping viable and profitable. The use of sodium sulfathiazole was eventually discontinued however because it didn't work against EFB, and when used for AFB, it left persistent residues in extracted honey.



In 1961 Bill Wilson developed the antibiotic patty method for applying chemical treatments to bee colonies. The patty consisted of heated honey, powdered sugar plus an antibiotic.



After nearly 45 years of excellent foulbrood control, a few cases of AFB that did not respond to Terramycin were reported in the US in 1996. In 1997, several honey bee colonies in Wisconsin were given heavy dustings of Terramycin and powdered sugar multiple times with no obvious reduction in the amount of AFB- diseased brood. The first reported cases were apparently in small bee operations in the northern Mid-Western states that were buying nucs in the spring and exchanging brood combs.



Some individuals have claimed that Terramycin extender patties caused P. larvae to become resistant to Terramycin. This is not correct since resistance first showed up in Argentina in the early 1990􏰑s where they were not using extender patties. Terramycin resistance also appeared in Canada in the late 1990s where they do not have a history of using Terramycin extender patties.



Although Terramycin can clean up AFB-diseased colonies if enough treatments are made over a long period of time, the best use of Terramycin is still prevention of AFB, especially in an apiary where an AFB colony had been identified.



Peter Loring Borst

Ithaca NY USA

peterloringborst.com

















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