Tielemans Eric, Rautenbach Carin, Viljoen Alta, Beugnet Frederic
Boehringer Ingelheim Animal Health, Lyon, France.
Clinvet International (Pty) Ltd., Bloemfontein, Republic of South Africa.
Parasit Vectors. 2025 Apr 15;18(1):142. doi: 10.1186/s13071-025-06787-y.
Canine babesiosis is a tick-borne disease of significant veterinary importance in dogs. It is caused by Babesia canis in Europe, where it is transmitted by Dermacentor reticulatus ticks.
A blinded, randomized, good clinical practice (GCP) and negative control experimental study was conducted to verify the efficacy of NexGard Spectra® in reducing the transmission of B. canis by D. reticulatus to dogs. NexGard Spectra® (IVP) is an oral product for dogs combining afoxolaner, an acaricide/insecticide compound from the isoxazoline class, and milbemycin oxime, a nematicide compound from the macrocyclic lactone class. Three groups of eight dogs were used; one group orally treated on day 0 with the IVP at the minimum recommended dose and two untreated control groups. On day 1, dogs from the treated group and from control group 1 were infested with 50 D. reticulatus adult ticks of 50/50 sex ratio infected with B. canis at a 23% infection rate. On day 28, dogs from the treated group and from control group 2 were infested similarly to those on day 1. Ticks were removed 6 days after each infestation.
Seven to nine days after each infestation, all untreated control dogs displayed clinical signs of canine babesiosis, i.e., lethargy, and/or dark urine, and/or > 39.5 °C rectal temperature. Blood was collected for microscopical blood smear examination, and for polymerase chain reaction (PCR) analysis. The blood smears from all untreated control dogs were positive for Babesia and all the PCR analyses were positive for B. canis. The control dogs were rescue treated. All control dogs were confirmed positive for B. canis by IFA on day 21 (control group 1) and on day 42 (control group 2). None of the IVP-treated dogs expressed any clinical sign of canine babesiosis following each of the two infestations of days 1 and 28 and until day 56. Blood was collected for IFA and PCR analyses from the treated dogs on days 21, 28, 42, and 56, and all results were negative.
In this study, the antiparasitic treatment prevented the transmission of B. canis to dogs following induced infestations.
犬巴贝斯虫病是一种对犬类具有重要兽医意义的蜱传播疾病。在欧洲，它由犬巴贝斯虫引起，通过网纹革蜱传播。
进行了一项盲法、随机、遵循良好临床规范（GCP）且设阴性对照的实验研究，以验证NexGard Spectra®在减少网纹革蜱将犬巴贝斯虫传播给犬类方面的功效。NexGard Spectra®（IVP）是一种用于犬类的口服产品，它将异恶唑啉类杀螨/杀虫剂化合物阿福拉纳与大环内酯类杀线虫剂化合物米尔贝肟结合在一起。使用三组，每组八只犬；一组在第0天以最低推荐剂量口服IVP进行治疗，另外两组为未治疗的对照组。在第1天，治疗组和对照组1的犬被50只感染犬巴贝斯虫且雌雄比例为50/50、感染率为23%的成年网纹革蜱叮咬。在第28天，治疗组和对照组2的犬接受与第1天类似的叮咬。每次叮咬后6天移除蜱虫。
每次叮咬后7至9天，所有未治疗的对照犬都出现了犬巴贝斯虫病的临床症状，即嗜睡、和/或尿液颜色加深、和/或直肠温度>39.5°C。采集血液进行显微镜血涂片检查和聚合酶链反应（PCR）分析。所有未治疗对照犬的血涂片巴贝斯虫检测呈阳性，所有PCR分析犬巴贝斯虫检测呈阳性。对照犬接受了挽救性治疗。所有对照犬在第21天（对照组1）和第42天（对照组2）通过间接荧光抗体试验（IFA）确诊为犬巴贝斯虫阳性。在第1天和第28天的两次叮咬后直到第56天，IVP治疗的犬均未表现出犬巴贝斯虫病的任何临床症状。在第21天、28天、42天和56天从治疗犬采集血液进行IFA和PCR分析，所有结果均为阴性。
在本研究中，抗寄生虫治疗可防止在人工感染后犬巴贝斯虫向犬类的传播。
