Vectra 3D (dinotefuran, pyriproxyfen and permethrin) prevents acquisition of Borrelia burgdorferi sensu stricto by Ixodes ricinus and Ixodes scapularis ticks in an ex vivo feeding model

Parasites & Vectors

Thomas Mather¹  Marie Varloud²  Djamel Tahir³  Leon Nicolaas Meyer³  Alec Evans³  Btissam Asri⁴  Byron Blagburn⁵  Valérie Choumet⁶  Reinhard K. Straubinger⁷  Frans Jongejan⁸ 

[1] Center for Vector-Borne Disease, University of Rhode Island, Kingston, RI, USA;Ceva Santé Animale, 10 Avenue de la Ballastière, 33500, Libourne, France;Clinvet Morocco, B.P 301, 28815, Mohammedia, Morocco;Clinvet Morocco, B.P 301, 28815, Mohammedia, Morocco;Institut Agronomique Et Vétérinaire Hassan II, Rabat, Morocco;College of Veterinary Medicine, Auburn University, 36849, Auburn, AL, USA;Environnement Et Risques Infectieux, Institut Pasteur, Paris, France;Institute for Infectious Diseases and Zoonoses, Bacteriology and Mycology, Faculty of Veterinary Medicine, Ludwig-Maximilians-University Munich, 80539, Munich, Germany;Vectors and Vector-Borne Diseases Research Programme, Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa;

关键词: Canine Lyme borreliosis;    Ixodes scapularis;    Ixodes ricinus;    Borrelia burgdorferi;    Blocking transmission;    Prevention;    Ex vivo model;   

DOI  :  10.1186/s13071-021-04881-5

来源: Springer

【 摘 要 】

BackgroundWe evaluated the efficiency of an ex vivo feeding technique using a silicone membrane-based feeding chamber to (i) assess the anti-feeding and acaricidal efficacy of a spot-on combination of dinotefuran, pyriproxyfen and permethrin (DPP, Vectra® 3D) against adult Ixodes scapularis and Ixodes ricinus ticks, and to (ii) explore its effect on blocking the acquisition of Borrelia burgdorferi sensu stricto.MethodsEight purpose-bred dogs were randomly allocated to two equal-size groups based on body weight assessed on day 2. DPP was administered topically, as spot-on, to four dogs on day 0. Hair from the eight dogs was collected individually by brushing the whole body on days 2, 7, 14, 21, 28 and 35. On each day of hair collection, 0.05 g of sampled hair was applied on the membrane corresponding to each feeding unit (FU). Seventy-two FU were each seeded with 30 adults of I. scapularis (n = 24 FU) or I. ricinus ticks (n = 48 FU). Bovine blood spiked with B. burgdorferi sensu stricto (strain B31) was added into each unit and changed every 12 h for 4 days. Tick mortality was assessed 1 h after seeding. One additional hour of incubation was added for live/moribund specimens and reassessed for viability. All remaining live/moribund ticks were left in the feeders and tick engorgement status was recorded at 96 h after seeding, and the uptake of B. burgdorferi s.s. was examined in the collected ticks by applying quantitative real-time PCR.ResultsExposure to DPP-treated hair was 100% effective in blocking B. burgdorferi s.s. acquisition. The anti-feeding efficacy remained stable (100%) against both Ixodes species throughout the study. The acaricidal efficacy of DPP evaluated at 1 and 2 h after exposure was 100% throughout the study for I. ricinus, except the 1-h assessment on day 28 (95.9%) and day 35 (95.3%). The 1-h assessment of acaricidal efficacy was 100% at all time points for I. scapularis.ConclusionsThe ex vivo feeding system developed here demonstrated a protective effect of DPP against the acquisition of B. burgdorferi without exposing the animals to the vectors or to the pathogen.Graphical Abstract

【 授权许可】

CC BY