title: A novel combination of fipronil and permethrin (Frontline Tri-Act®/Frontect®) reduces risk of transmission of Babesia canis by Dermacentor reticulatus and of Ehrlichia canis by Rhipicephalus sanguineus ticks to dogs.
abstract: BACKGROUND
  The ability of Frontline Tri-Act®/Frontect®, a topical ectoparasiticide containing fipronil and permethrin for dogs, to prevent the transmission of Babesia canis as well as Ehrlichia canis was evaluated by infesting dogs with infected vector ticks.
  
  
  METHODS
  For the Babesia canis study, 16 dogs were randomly allocated to two groups. Eight dogs were treated on day 0 with a topical spot-on formulation containing 6.76 % w/v fipronil plus 50.48 % w/v permethrin and eight dogs served as the untreated control group. Dermacentor reticulatus ticks, with a B. canis infection rate ranging between 2 and 10 %, were placed onto dogs on days 7, 14, 21 and 28. In situ tick counts were performed on Days 9, 16 and 23. Ticks were counted and removed on Day 30. Infection of the dogs with B. canis was monitored by rectal temperature readings, clinical examinations and blood smears as well as PCR and IFA (indirect fluorescent antibody assay). For the Ehrlichia canis study, another 16 dogs were allocated to two groups. Eight dogs were treated with the fipronil and permethrin combination on days 0 and 28 and eight dogs served as untreated controls. Rhipicephalus sanguineus ticks, carrying an infection rate of 13 % for E. canis, were released in the sleeping kennels of the dogs on days 7, 14, 21, 28, 35, 42, 49 and 56. Ticks were counted in situ on the dogs on a weekly basis. All ticks were removed and counted on the final assessment day 58. Infection of the dogs with E. canis was monitored by rectal temperature, clinical examinations, and testing of blood samples by PCR, IFA and platelet counts.
  
  
  RESULTS
  B. canis was transmitted by D. reticulatus ticks to all eight untreated control dogs and to one treated dog, which was confirmed by blood smears, PCR and IFA. E.canis was transmitted by R. sanguineus ticks to all eight untreated control dogs. Two of the dogs in the treated group were found positive based on PCR and/or IFA.
  
  
  CONCLUSIONS
  Frontline Tri-Act®/Frontect® significantly lowered the risk for dogs to acquire a B. canis infection by 87.5 % over a challenge period of 28 days. The risk for dogs to acquire E. canis was reduced by 75 % over a period of 56 days.
authors.affiliation: Utrecht Centre for Tick-borne Diseases (UCTD), FAO Reference Centre for Ticks and Tick-borne Diseases, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584, CL, Utrecht, The Netherlands. F.Jongejan@uu.nl.|Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa. F.Jongejan@uu.nl.
authors.forename: Frans
authors.initials: F
authors.lastname: Jongejan
authors.affiliation: ClinVet International (Pty) Ltd, P.O. Box 11186, Universitas, Bloemfontein, 9321, Republic of South Africa. Christa.devos@clinvet.com.
authors.forename: Christa
authors.initials: C
authors.lastname: de Vos
authors.affiliation: ClinVet International (Pty) Ltd, P.O. Box 11186, Universitas, Bloemfontein, 9321, Republic of South Africa. Josephus.Fourie@clinvet.com.
authors.forename: Josephus J
authors.initials: JJ
authors.lastname: Fourie
authors.affiliation: Merial S.A.S., 29 Av Tony Garnier, 69007, Lyon, France. Frederic.Beugnet@merial.com.
authors.forename: Frederic
authors.initials: F
authors.lastname: Beugnet
mesh_terms: D000818:Animals; D001403:Babesia / Q000302:isolation & purification; D001404:Babesiosis / Q000517:prevention & control* / Q000635:transmission; D003870:Dermacentor / Q000187:drug effects / Q000469:parasitology; D018562:Disease Transmission, Infectious / Q000517:prevention & control; D004283:Dog Diseases / Q000188:drug therapy*; D004285:Dogs; D004338:Drug Combinations; D004478:Ectoparasitic Infestations / Q000188:drug therapy / Q000662:veterinary*; D041061:Ehrlichia canis / Q000302:isolation & purification; D016873:Ehrlichiosis / Q000517:prevention & control* / Q000635:transmission; D007306:Insecticides / Q000008:administration & dosage*; D026023:Permethrin / Q000008:administration & dosage*; D011720:Pyrazoles / Q000008:administration & dosage*; D048508:Rhipicephalus sanguineus / Q000187:drug effects / Q000469:parasitology; D016896:Treatment Outcome
chemical_list: D004338:Drug Combinations; D007306:Insecticides; D011720:Pyrazoles; D026023:Permethrin; C082360:fipronil