deknow wrote:
> our thesis is that since the introduction of varroa, the number of substances that beekeepers are willing to put in the hives has increased dramatically...

This thesis is supported by neither any data nor a close reading of
history. The use of disinfectants to combat disease in the silkworm is
fairly old:

> In 1835, an Italian lawyer, who had interested himself in biology, had discovered that a fungus caused the silkworm disease of muscardine. He was the first investigator to identify a well known animal disease with an identified micro-organism. He also interested himself in antiseptics and disinfectants and investigated acids, alkalies, chlorine, sulphur, alcohol, the products available to him at that time. In 1881 Koch examined 70 compounds for their antibacterial activity. He declared that mercuric chloride was the best of them. Indeed, it was the only substance that killed bacterial spores.

In the 1903 ABC XYZ of Bee Culture,  Root talks about using
disinfectants against foul brood. He states that:

> Carbolic acid, phenol, thymol, salicylic acid, naphthol beta, perchloride of mercury as well as many other substances have been tried. ... There are certain substances which evaporate at the ordinary temperatures of the hive, and whose vapors, while not actually killing the bacilli, arrest their increase or growth. Among such substances are carbolic acid, phenyl, lysol, eucalyptus, camphor, napthalene among others.

The use of carbolic acid on bees, which continues to this day, has its
roots at the dawn of modern disease treatment:

> Lister became aware of a paper published (in French) by the French chemist Louis Pasteur which showed that rotting and fermentation could occur without any oxygen if micro-organisms were present. If micro-organisms were causing gangrene, the problem was how to get rid of them. Pasteur suggested three methods: to filter them out, to heat them up, or expose them to chemical solutions.

> The first two were inappropriate in a human wound so Lister experimented with the third. Carbolic acid (phenol) had been in use as a means of deodorizing sewage, so Lister tested the results of spraying instruments, the surgical incisions, and dressings with a solution of it. Lister found that carbolic acid solution swabbed on wounds markedly reduced the incidence of gangrene. Some consider Lister "the father of modern antisepsis".

-- 
Peter L Borst
Danby, NY USA
42.35, -76.50
http://picasaweb.google.com/peterlborst

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