title: The ability of a topical novel combination of fipronil, amitraz and (S)-methoprene to protect dogs from Borrelia burgdorferi and Anaplasma phagocytophilum infections transmitted by Ixodes scapularis.
abstract: Healthy, purpose-bred laboratory beagle dogs that had not been exposed to ticks and were seronegative for Borrelia burgdorferi and Anaplasma phagocytophilum were randomly assigned to four groups of eight dogs each. Control group 1 was not treated. Groups 2, 3 and 4 were treated with a single topical application of a new formulation of fipronil, amitraz and (S)-methoprene (CERTIFECT™, Merial Limited, GA, USA) at 28, 21 or 14 days prior to tick infestation, respectively. Each dog was infested with 25 female and 25 male field-collected adult Ixodes scapularis ticks that had infection rates of 66% for B. burgdorferi sensu stricto and 23% for A. phagocytophilum, as determined by polymerase chain reaction. Two and five days after tick infestation, control dogs had an average of 9.5 and 13.9 attached adult female ticks, respectively, whilst the 24 treated dogs remained tick-free aside from a single tick on the 2nd day after infestation. Serial serological tests demonstrated that the ticks successfully infected 8/8 control dogs with B. burgdorferi and co-infected 6/8 with A. phagocytophilum. B. burgdorferi infection also was confirmed in most control dogs by culture (6/8) and PCR (7/8) of skin biopsies. In contrast, CERTIFECT protected all 24 treated dogs against infection by both B. burgdorferi and A. phagocytophilum, as demonstrated by their negative serological tests throughout the study and the absence of any positive skin biopsy culture or PCR in these dogs.
authors.affiliation: TRS Labs, Inc., PO Box 5112, Athens, GA, USA.
authors.forename: John W
authors.initials: JW
authors.lastname: McCall
authors.forename: Christine F
authors.initials: CF
authors.lastname: Baker
authors.forename: Thomas N
authors.initials: TN
authors.lastname: Mather
authors.forename: S Theodore
authors.initials: ST
authors.lastname: Chester
authors.forename: Scott D
authors.initials: SD
authors.lastname: McCall
authors.forename: Jennifer P
authors.initials: JP
authors.lastname: Irwin
authors.forename: Stephanie L
authors.initials: SL
authors.lastname: Young
authors.forename: Luiz G
authors.initials: LG
authors.lastname: Cramer
authors.forename: Matthias G
authors.initials: MG
authors.lastname: Pollmeier
mesh_terms: D000287:Administration, Topical; D041081:Anaplasma phagocytophilum / Q000502:physiology; D000818:Animals; D000907:Antibodies, Bacterial; D001096:Arachnid Vectors / Q000187:drug effects* / Q000382:microbiology / Q000502:physiology; D025065:Borrelia burgdorferi / Q000502:physiology; D004283:Dog Diseases / Q000188:drug therapy / Q000469:parasitology / Q000517:prevention & control* / Q000635:transmission; D004285:Dogs; D004311:Double-Blind Method; D004338:Drug Combinations; D016873:Ehrlichiosis / Q000469:parasitology / Q000517:prevention & control / Q000635:transmission / Q000662:veterinary; D005260:Female; D007306:Insecticides / Q000494:pharmacology / Q000627:therapeutic use*; D018884:Ixodes / Q000187:drug effects* / Q000382:microbiology / Q000502:physiology; D008193:Lyme Disease / Q000469:parasitology / Q000517:prevention & control / Q000635:transmission / Q000662:veterinary; D008297:Male; D008726:Methoprene / Q000494:pharmacology / Q000627:therapeutic use; D011720:Pyrazoles / Q000494:pharmacology / Q000627:therapeutic use; D012237:Rhode Island; D013983:Tick Control / Q000379:methods; D013984:Tick Infestations / Q000188:drug therapy / Q000469:parasitology / Q000517:prevention & control / Q000662:veterinary*; D013997:Time Factors; D014052:Toluidines / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D000907:Antibodies, Bacterial; D004338:Drug Combinations; D007306:Insecticides; D011720:Pyrazoles; D014052:Toluidines; C014983:amitraz; D008726:Methoprene; C082360:fipronil