86 Drug Treatment of East Coast Fever of Cattle 
Summary and Conclusions. 
No drug has been found which will influence the fatal course of 
East Coast Fever or retard the multiplication of Theileria parva in the 
blood of the affected cattle. 
The drugs which were tried with negative results were Trypanblue, 
Congo red, Tryposafrol, Creosote and Oleum copaivae, Arsacetin, 
Soamin, “606,” Emetine hydrochloride. Mercury salicylate. Mercury 
succinimide. Quinine bihydrochloride and hydrochloride, Ethylhydro- 
cupreine. Ammonium fluoride. Potassium iodide. Sodium sahcylate. 
Calcium lactate, and Nuclein. 
All of our animals died—18 treated and 3 untreated—and showed 
typical lesions at autopsy. They were all infected by means of ticks 
{Rhipicephalus appendiculatus) which had fed on infected cattle as 
larvae and nymphs and been placed on the experimental animals as 
nymphs and adults respectively. 
The increase in the number of parasitized red blood corpuscles, but 
for slight irregularities, proceeds continuously night and day until the 
animal dies. We have not as yet observed a case ending in recovery. 
The accompanying table gives a summary relating to each experi¬ 
mental animal (except XII): the number and kind of ticks which 
produced infection, the incubation period, the time when the parasites 
appeared in the peripheral blood, the time when the animals died, 
and the maximum percentage of parasitized blood corpuscles observed 
during the course of the disease. The days are all reckoned from Day 1 
when the infective ticks were placed upon the cattle. 
The expenses of this investigation were mainly defrayed by means 
of a grant made by the Parliament of the Union of South Africa. 
My thanks are due to Dr W. E. Dixon, F.E.S., University Lecturer 
in Pharmacology, Cambridge, for kindly suggesting the trial of several 
of the drugs which were used. I am also indebted to my Laboratory 
Assistant, Mr B. G. Clarke, for much valuable help, especially in the 
making of the blood counts. 
