Bob H. wrote in response to what Geroge posted;
The scenario above would have been quite different if we had had another 98%
control chemical (of a completely different chemical makeup) to alternate
with Apistan would it not George?  Be honest.

How long in your estimation would Fluvalinate taken to become ineffective if
alternated with another 98% control chemical ( we did have two completely
different chemicals available at the start of varroa mite treatment in the
U.S. - Coumaphos & Fluvalinate) ?

George wrote in an earlier post;
The result is that as soon as an pesticide enters the body of the insect, it
is broken down so efficiently that the poisons never reach their  target
tissue to cause death.

My reply if I may;

Bob, considering what George stated, in my opinion, it would not have helped
to have a another 98% control chemical (of a completely different chemical
makeup) to alternate with Apistan. Why, because of this that George wrote
earlier assuming he was correct;

"This occurs because the DDT-R gene becomes mutated by insertion of another
piece of the fly's DNA known as a jumping gene, into the controlling
sequence of the gene.This insertion messes up the normal expression of
DDT-R, leading to over production of its product, the cytochrome P450
metabolic enzyme."

It would have happened anyway with either poison even if used alternated. It
was not hard for me to figure that poisons did not belong in a bee hive
unless you want them to eventually die. Even though I never have used
poisons in my hives my bees needed help controlling Varroa. With the
mentoring of Dee & Ed Lusby I feel I am on the right path now. You can take
my opinion as a grain of salt, at least I am not poisoning my bees.
  .  ..
c(((([
Keith Malone
Chugiak, Alaska USA