The ability of an oral formulation of afoxolaner to block the transmission of Babesia canis by Dermacentor reticulatus ticks to dogs

Particle and Fibre Toxicology

Josephus Fourie¹  Heidi Erasmus¹  Michel Labuschagné¹  Diane Larsen²  Lenaig Halos²  Frederic Beugnet² 

[1] ClinVet International (Pty) Ltd, P.O. Box 11186, Universitas, Bloemfontein 9321, Republic of South Africa;Merial S.A.S., 29 Av Tony Garnier, 69007 Lyon, France

关键词: Afoxolaner;    Transmission blocking;    Dermacentor reticulatus;    Dogs;    Babesia canis;   

Others  :  803972
DOI  :  10.1186/1756-3305-7-283

 received in 2014-04-07, accepted in 2014-06-03,  发布年份 2014

【 摘 要 】

Background

Canine babesiosis due to Babesia canis is an endemic disease in many European countries. A vaccine is available in some countries, but it does not prevent the infection and just helps in reducing the gravity of clinical signs. Therefore, the major way to help preventing the disease is by controlling tick infestations on dogs.

To assess the preventive efficacy of afoxolaner (NexGard®), a new oral anti- flea and tick product, against Babesia canis infected adult Dermacentor reticulatus in an experimentally controlled study.

Methods

Sixteen healthy mixed breed adult dogs, negative for Babesia canis antibodies were included in a single centre, randomized, blinded and controlled study to evaluate the impact of treatment with afoxolaner on the transmission of Babesia canis to dogs exposed to Dermacentor reticulatus. The dogs were randomly allocated into two groups of 8 dogs each. One group remained untreated. In the other group, dogs were treated orally with a novel formulation of afoxolaner (NexGard®) on day 0. All dogs were infested each by 50 adult Dermacentor reticulatus ticks (equal sex ratio) at days 7, 14, 21 and 28. The Dermacentor reticulatus ticks were confirmed to harbour Babesia canis by Polymerase Chain Reaction (PCR).

Results

The treatment was well tolerated by all dogs without any adverse effects. Babesia canis was transmitted by D. reticulatus to all untreated control dogs, confirmed following demonstration of hyperthermia, detection of B. canis parasites in blood smears and PCR assay from blood and serology. These confirmed infected dogs were subsequently treated with imidocarb and diminazene. The treated dogs remained negative based on all criteria until the last study, Day 56, confirming that the oral treatment of dogs with NexGard® prevented transmission of Babesia canis and development of clinical babesiosis for up to 28 days.

Conclusion

This is the first demonstration that an oral acaricidal treatment may prevent the transmission of a pathogen despite the need for the tick to attach and start feeding before being killed by the acaricide.

【 授权许可】

   
2014 Beugnet et al.; licensee BioMed Central Ltd.

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