were are going to discuss the frustration with fleas.
Yes, those little blood-sucking parasites ravaging our
companions and making their lives miserable.
that is a bit dramatic, but fleas actually can be very
frustrating, both for our companions and for us as
the last couple of years, I have noticed a problem with
flea control, especially in dogs.
who are committed to regular flea prevention for their
dogs still are seeing their dogs scratching and biting
at themselves in response to flea infestations on their
bodies. What gives?
is occurring is a classic biologic response within the
flea population. It is called adaptation and it occurs
in all species of animals. When a species of animal is
faced with a change in its environment, it must deal
with that change.
the case of fleas, they have been challenged with
various chemicals designed to kill them. Most of them
have obliged and died. In fact, in the past decade or
so, with the advent of a product for flea control called
fipronil — most commonly under the brand name
Frontline — we have been quite successful dealing with
fleas. This period of success, however, is waning.
seems after years of exposure to Frontline, fleas have
become resistant to its mechanism of action to kill
them. How does this happen, you might ask?
adaptation is the answer. This is a genetic phenomenon
that allows a species, in this case fleas, to
genetically alter themselves in response to an
environmental change in this case is the addition of
Frontline to the flea’s environment: the dog.
in simple terms, when Frontline was first used, it was
extremely effective in killing fleas in our companions.
Many generations of fleas were exposed and died, but
every once in a while there were some that were
genetically resistant to Frontline.
resistance was of no advantage (no pun intended) to
these particular fleas until they were exposed to
Frontline. Those fleas without this genetic resistance
died when exposed to Front-line, those with it did not.
then did what every species is supposed to do: They bred
and thus passed on this resistance to Frontline to their
offspring. This resistance was genetically multiplied
within the flea population and over many generations and
several years of time, we now have a significant
population of fleas that can tolerate Frontline.
is a very simplified illustration, but nonetheless
applicable. Incidentally, this is the same thing that
occurs in bacterial populations that become resistant to
then what are we supposed to do with these resistant
fleas that are sucking the blood out of our companions?
have to use a new product to which the fleas have not
had a chance to develop resistance. I am currently
recommending Activyl with the active ingredient
far, it has been extremely effective in preventing flea
bites and bringing overall relief.
I know what some of you are thinking: What is to prevent
fleas from becoming resistant to Activyl?
answer is, nothing. We just hope it won’t be for
several years while work is being done on the next flea
prevention medication for our companions.