24 
Poisonous Arthropods 
It seems clearly established that the bite of certain ticks may 
cause a temporary paralysis, or even complete paralysis, involving 
the organs of respiration or the heart, and causing death. In 1912, 
Dr. I. U. Temple, of Pendleton, Oregon, reported several cases of 
what he called “acute ascending paralysis” associated with the occur¬ 
rence of ticks on the head or the back of the neck. A typical severe 
case was that of a six year old child, who had retired in her usual 
normal health. The following morning upon arising she was unable 
to stand on her feet. She exhibited paralysis extending to the knees, 
slight temperature, no pain, sensory nerves normal, motor nerves 
completely paralyzed, reflexes absent. The following day the paral¬ 
ysis had extended to the upper limbs, and before night of the third 
day the nerves of the throat (hypoglossal) were affected. The thorax 
and larynx were involved, breathing was labored, she was unable 
to swallow liquids, phonation was impossible and she could only make 
low, gutteral sounds. At this stage, two ticks, fully distended with 
blood, Were found over the junction of the spinal column with the 
occipital bones in the hollow depression. They were removed by 
the application of undiluted creoline. Though the child’s life was 
despaired of, by the following morning she was very much improved. 
By evening she was able to speak. The paralysis gradually receded, 
remaining longest in the feet, and at the end of one week the patient 
was able to go home. 
There was some doubt as to the exact species of tick implicated 
in the cases which Dr. Temple reported, although the evidence 
pointed strongly to Dermacentor venustus.* Somewhat later, Hadwen 
(1913) reported that “tick paralysis” occurs in British Columbia, 
where it affects not only man, but sheep and probably other animals. 
It is caused by the bites of Dermacentor venustus and was experi¬ 
mentally produced in lambs and a dog (Hadwen and Nuttall, 1913). 
It is only when the tick begins to engorge or feed rapidly, some days 
after it has become attached, that its saliva produces pathogenic 
effects. 
Ulceration following tick bite is not uncommon. In many of the 
instances it is due to the file-like hypostome, with its recurved teeth, 
being left in the wound when the tick is forcibly pulled off. 
*According to Stiles, the species occurring in the Northwest which is commonly 
identified as D. venustus should be called D. andersonii (see footnote, chapter 12). 
