10% Imidacloprid/50% Permethrin (ImPer, advantix^®) prevents Ehrlichia canis infection in treated dogs, a new study shows.

Domenico Otranto, of the University of Bari, Valenzano, and associates between January and March 2005 screened 845 dogs from two kennels in southern Italy (kennels of Bari (KB)- and Ginosa (KG)) for their study.

The dogs had a history of tick infestation and were initially tested by serology and PCR assay for E. canis infection. From a previous study carried out on the same dog population data on Leishmania infantum infection were also available, the scientists note.

While in Bari 65 dogs presented anti-E. canis antibodies (15.6%), in Ginosa 61 dogs were positive for anti-E. canis antibodies (14.2%).

The investigators enrolled 535 animals found negative both for E. canis and L. infantum infections in three groups (Group A—treated with ImPer once a month; Group B—treated every 2 weeks; and Group C—untreated control animals) and tested them for E. canis infection by serology and PCR in November 2005 (first follow-up) and in March 2006 (second follow-up).

According to the findings, published online on February 16th in Veterinary Parasitology, E. canis infection was serologically revealed at the first and/or second follow-up in 26 animals from Group C in KB and KG (mean incidence density rate (IDR), 13.24%), but in none of the animals from Group A (KB and KG) and only in one animal from Group B (IDR 1.13%) in KG.

Therefore, the final protection efficacy of ImPer ranged from 95.57% to 100% in Groups B and A, the investigators note.

Furthermore, Otranto’s team observed that only 15 dogs from KG were positive for Rickettsiales only at the first follow-up and at the sequence analysis 2 (both in Group C) revealed 100% homology with E. canis sequences, the other 13 with Anaplasma platys, of which 4 were also seropositive for E. canis at one or both follow-ups.

“ImPer, by virtue of its repellent and acaricidal activity against ticks, has been shown to be efficacious to prevent E. canis infection in treated dogs living under natural conditions in endemic areas,” the researchers conclude.

References

• Veterinary Parasitology 2008, available online 16 February
  Article in Press, Corrected Proof
  doi:10.1016/j.vetpar.2008.02.008