Has advantix been shown to be very efficacious against fleas?

Yes. advantix has excellent activity against fleas and provides efficacy of 99 to 100% for a period of up to one month. The larvicidal activity of imidacloprid has also been demonstrated.

Why is the anti-feeding effect important for an insecticide like imidacloprid?

Adult female fleas are great, speedy and aggressive eaters, consuming in one day a quantity of blood equal to 15 times their own body weight; while they are feeding they are inoculating the host with their saliva and also with possible pathogens which they are carrying.
By anti-feeding effect is meant the ability to reduce the ability of the flea to feed.
The rapidity of action of imidacloprid (within about three to five minutes the fleas stop their meal of blood and then they die) results in a rapid reduction in flea bites and efficacious elimination of the infestation.
This normally results in resolution of Allergic Flea-induced Dermatitis (AFD) and the halting of transmission of diseases related to the bites of these insects.

Why is imidacloprid efficacious in reducing the signs and symptoms of FAD?

Imidacloprid remains localised in the lipid stratum which covers the surface of the skin and it kills the adult fleas by absorption through the intersegmental membranes. Research has shown that the fleas are poisoned within three to five minutes and die within about an hour; the combination of these effects - rapidity of action and marked efficacy - eliminates the aetiological agent, resolving the signs and symptoms which are linked to this parasitosis.

How does imidacloprid act on the larval forms of fleas?

Clinical and laboratory studies have shown that imidacloprid is distributed over the surface of the skin of treated animals. In the environment in which the animal lives, physiological cutaneous exchange disperses the cutaneous detritus (scurf) which carries infinitesimal quantities of imidacloprid.
This cutaneous detritus is the main food for the larvae, which die when they ingest it.

How is imidacloprid absorbed by the fleas?

In vitro studies have shown that imidacloprid is transferred to the fleas after brief contact which these have with the skin and coat of the treated animal. This absorption occurs through the fine intersegmental membranes which enable the insects to move.

What kinds of fleas are most often found in exotic animals?

Generally speaking, if an exotic pet (rabbit, ferret, guinea pig, etc.) has fleas, one needs to investigate whether it is an animal which lives in a flat and has contact with other domestic animals; in this case the fleas which can be found are of the same groups which commonly infest dogs and cats.
If the animal is living in the wild, it will very probably be infested by host-specific fleas.
In the case of an animal living in the house, it will be necessary to implement a parasite control strategy which involves environmental treatment associated with treatment of all the animals living together.

May the efficacy of an anti-flea treatment be different for the different types of fleas?

Generally speaking, the efficacy of imidacloprid in the various most common types of flea is superimposable.
However, differences in efficacy may be found related to the diversity of coat and skin in the treated animals; efficacy is always however guaranteed to be 99% in the fourth week.

advantix does not appear to have the same efficacy on fleas as Advantage; why is this? Is there some interaction between the two active substances which may be the cause of it?

Some owners say they have seen fleas on the dog after 10 to 14 days; why?

Particularly during the initial treatment with advantix in a dog which is already infested, one needs to remember that the adult fleas present on the animal generally account for only 5% of the total population of fleas present in the environment at the different stages of their life cycle. This means that some time is required for the infestation present in the environment in which the dog lives to be eradicated. In fact when one takes steps by killing the adult parasites, there will be a proportion of fleas at the pupal stage waiting to mature and come out on the dog; it is therefore possible that some new adults, generally in the first month after the application, will discover the animal.
The larvicidal activity in the environment in which the dog lives will, within a short time, reduce the population of larvae which mutate to the pupal stage. The dual activity on adults and larvae will in time produce resolution of the infestation. It is estimated that for the action to be complete, with total disappearance of the fleas at every stage of their development in an environment habitually frequented by infested animals (Pupal Window Effect), this may take three to four weeks.