title: Apparent tick paralysis by Rhipicephalus sanguineus (Acari: Ixodidae) in dogs.
abstract: Certain tick species including Ixodes holocyclus can inoculate neurotoxins that induce a rapid, ascending flaccid paralysis in animals. Rhipicephalus sanguineus, the most widespread tick of dogs, is recognized as a vector of several pathogens causing diseases in dogs and humans. A single report suggests its role as cause of paralysis in dogs. This study presents the clinical history of 14 young dogs heavily infested by R. sanguineus (intensity of infestation, 63-328) in an endemic area of southern Italy. During May to June of 2011, dogs were presented at the clinical examination with neurological signs of different degrees (e.g., hind limb ataxia, generalized lethargy, and difficulty in movements). All animals were treated with acaricides and by manual tick removal but ten of them died within a day, displaying neurological signs. The other 4 dogs recovered within 3 days with acaricidal and supportive treatment. Twelve dogs were positive by blood smear examination for Hepatozoon canis with a high parasitemia, two also for Babesia vogeli and two were negative for hemoparasites. Low-grade thrombocytopenia, hypoalbuminemia, and pancytopenia were the haematological alterations most frequently recorded. Other causes of neurological disease in dogs were excluded and the diagnosis of tick paralysis by R. sanguineus was confirmed (ex juvantibus) by early and complete recovery of 4 dogs following acaricidal treatment and tick removal.
authors.affiliation: Dipartimento di Sanità Pubblica e Zootecnia, Università degli Studi di Bari, Valenzano, BA, Italy. d.otranto@veterinaria.uniba.it
authors.forename: Domenico
authors.initials: D
authors.lastname: Otranto
authors.forename: Filipe
authors.initials: F
authors.lastname: Dantas-Torres
authors.forename: Viviana Domenica
authors.initials: VD
authors.lastname: Tarallo
authors.forename: Rafael Antonio do Nascimento
authors.initials: RA
authors.lastname: Ramos
authors.forename: Dorothee
authors.initials: D
authors.lastname: Stanneck
authors.forename: Gad
authors.initials: G
authors.lastname: Baneth
authors.forename: Donato
authors.initials: D
authors.lastname: de Caprariis
mesh_terms: D056810:Acaricides / Q000627:therapeutic use*; D000818:Animals; D004283:Dog Diseases / Q000188:drug therapy / Q000401:mortality / Q000469:parasitology*; D004285:Dogs; D005260:Female; D007558:Italy / Q000453:epidemiology; D008297:Male; D008726:Methoprene / Q000008:administration & dosage; D018512:Parasitemia; D011720:Pyrazoles / Q000008:administration & dosage; D048508:Rhipicephalus sanguineus / Q000187:drug effects / Q000502:physiology*; D013984:Tick Infestations / Q000188:drug therapy / Q000469:parasitology / Q000662:veterinary*; D013985:Tick Paralysis / Q000401:mortality / Q000469:parasitology / Q000662:veterinary*
chemical_list: D056810:Acaricides; D011720:Pyrazoles; D008726:Methoprene; C082360:fipronil