105 



biliary fever to be a tick-borne disease in South Africa, the carrier 

 being Rhipicephalus evertsi. As neither of these ticks is known in 

 India, the intermediate host still remains to be discovered there. 

 Belitzer has recommended that all young equine stock should be 

 exposed to tick infection, whereby they would acquire a natural 

 immunity. 



NuTTALL (G. H. F.). Tick Paralysis in Man and Animals. — 



Parasitology, Cambridge, vii, no. 1, May 1914, pp. 95-104. 



Since the appearance of the last papers by himself and Hadwen 

 on tick paralysis [see this Review, Ser. B. i, p. 204], the author 

 has obtained more evidence on the subject, from a paper by 

 Borthwick, on its occurrence in sheep, and from another by 

 Dr. Temple of Pendleton, Oregon, dealing with its occurrence 

 in man. The present paper contains abstracts from these two con- 

 tributions, giving the clinical details and points of interest regarding 

 transmission in the various cases described, and discussing the bearing 

 of these data upon the present state of our knowledge. Regarding 

 the disease in sheep, the papers by Mally (1904) and Borthwick attri- 

 bute a disease called " tick paralysis " in sheep in Cape Colony, to the 

 animals being attacked by Ixodes 2jilosi(s, Koch. Both authors state 

 that farmers in Cape Colony have no doubt as to the bearing of the 

 tick upon infection ; the use of Cooper's dip has served to check the 

 disease in flocks attacked by paralysis, and to prevent the affection 

 in animals exposed in localities where it prevails. The disease has a 

 seasonal incidence, is acute in it sonset, and recovery occurs rapidly 

 in most cases. Fever is absent and the disease is not communicable 

 by blood inoculation. Recovery is hastened by the removal of ticks. 

 In animals that have died from the disease, no noticeable patho- 

 logical lesions are observable. The author says that in the absence of 

 further data, these observations cannot be regarded as more than 

 suggestive, but that the paper by Hadw^en has thrown much light on 

 the subject, as he not only observed a practically identical disease in 

 sheep in British Columbia, but has also reproduced it experimentally 

 by means of ticks {Dermacentor venustus, Banks). 



That a similar affection appears to occur in other animals in British 

 Columbia has been indicated by Hadwen, and Hadwen and Nuttall 

 reproduced the disease in a dog in Cambridge, the ticks {D. venustus) 

 having been collected from a human subject near Nelson, British 

 Columbia. Todd cites cases of tick paralysis occurring in five children 

 and one adult in British Columbia, assuming that the tick was 

 D. venustus. Eaton cites a case in a child in Australia, the tick being 

 undetermined. Since tick paralysis has been reproduced experi- 

 mentally there is no doubt as to the existence of the disease. The 

 symptoms described in the human subject agree with those observed 

 in experimental cases in the sheep and dog, and with the symptoms 

 noted in cases occurring in sheep in the field. The author refers to 

 the general weakness of the data as to the exact species of tick concerned 

 in the causation of the human cases. Todd and Temple merely refer 

 to " ticks " ; Temple sent three ticks for determination and they 

 proved to be Dermacentor albipictus, D. venustus, and Ornithodoru^ 

 megnini respectively ; the last-mentioned species has probably nothing 

 (C47) Ai2 



