Five-month serological monitoring to assess the effectiveness of permethrin/fipronil (Frontline Tri-Act®) spot-on in reducing the transmission of Leishmania infantum in dogs

In addition, this trial provided means to serological assess the transmission of other vector-borne pathogens. Regarding Anaplasma spp., one dog in each group was seropositive at the beginning of the study and no dogs became positive during the study. For Ehrlichia canis, 9/25 (36%) dogs in group 1 and 5/31 (16.1%) in group 2 were seropositive at inclusion time. Two out of 16 (11.8%) and 3/26 (11.5%) dogs became positive for E. canis after 3 months in groups 1 and 2, respectively. No Borrelia burgdorferi sensu lato seropositive dog was found during the study. In regard to Dirofilaria immitis, 7/25 (28%) dogs and 12/31 (38.7%) were antigen-positive in groups 1 and 2, respectively, at inclusion. There was no significant difference between groups 1 and 2 in regard to new seroconversions during the trial. This study, conducted in a highly endemic area for vector-borne pathogen transmission, confirmed that the use of deltamethrin and permethrin is a suitable approach to reduce the risk of L. infantum infection by sandflies.