TRYPANOficnriAsrs ix the AxrfEo-EaYPTiAx Shhan 
By the Director 
Nearly all the records of trypanosomiasis work, and especially the experimental work 
on therapeutics carried out by me alone and in conjunction with Mr. Archibald, were 
destroyed by fire, hence this Eeport has had to bo much curtailed. 
Considering for a moment the work dealt with in the last Report, one may note that 
chrysoidin appeared to be quite as effectual in human trypanosomiasis given by the mouth 
as given hypodermically, but, as mentioned, the drug has the disadvantage of irritating the 
kidneys, and in any case failed to cure monkeys infected with T. ijambiense. The case of 
human trypanosomiasis appeared to improve under its use, but unfortunately the patient 
sustained an injury to his leg, which resulted in a general septicifiiiiia that proved fatal, 
despite careful surgical treatment in the Military Hospital, Khartoum. It is worth noting 
that at no time during his illness could trypanosomes be demonstrated in his peripheral 
blood. 
No other cases of human trypanosomiasis, or sleeping sickness, have been available, 
but, thanks to the kindness of Drs. Stephens and Breinl, of the Liverpool School of Tropical 
^Medicine, we were put in possession of a strain of T. gamhieiise. It was found that gerbils 
(Gerbilliis pijgargiis) could readily be inoculated and they were used in the subseqirent work, 
the object of which was to test the value of one of the new organic arsenical salts of the 
aromatic series, namely ‘ Orsudan,’ which is Sodium 3-niethyl-4-acetylaminophenyl- 
arsonate, and has the chemical formula :— 
vOH 
(GH . GO) . NH— >-As=0 
I "ONa 
CH3 
.\rsonates have the general formula RAsO(On)o. ‘Orsudan’ is anhydrous and contains 
2o-4 per cent, of arsenic. It is soluble in three times its weight of water, yielding a neutral 
solution. It is considerably less toxic than atoxyl, and is the least poisonous of the 
three allied salts recently placed on the market. The others are ‘Soamin’ (Sodium 
para-aminophenylarsonate) and ‘Kharsin’ (Sodiuin-3-inethyl-4-aminophenylarsonate). {See 
Dr. Wenyon’s Report.) ‘ Orsudan ’ is only one-fifth or one-sixth as toxic as ‘ Soamin.’ 
Having been successfully employed in syiihilis, and as they resemble atoxyl, it was thought 
advisable to try them in tiypanosomiasis. I selected ‘ Orsudan ’ for experimental work, 
and proceeded to ascertain its lethal dose for gerbils, and to employ it in the case of animals 
infected with T. gauibieuse (Liverpool strain) and the trypanosome of mule trypanosomiasis. 
At a later date, Mr. Archibald was associated with me in this work, and it is exceedingly 
unfortunate that all our papers were destroyed and that all the strains were lost. As a 
result, one cannot give the results obtained in detail while the work was cut short just 
when things looked somewhat promising. It was found that a healthy gerbil of average 
weight— about 40 grammes—could be given as a rule 1 c.c. of a 4 per cent, solution of 
‘ Orsudan ’ without a lethal effect being produced. 
In the case of infected animals, care was taken only to employ those whicli had been 
infected for some days, showed trypanosomes in their peripheral blood and liad begun to 
lose weight. This is in accordance with the regulations followed by Breinl, Todd and 
Kinghorn. 
So far as can be told, there was a difference in their reaction to tlie drug between gerbils 
inoculated with T. (/ambienae, and those inoculated with the mule trypanosome (so-called), 
‘ Orsudan ’ as 
a therapeutic 
agent 
The arsonates 
