L'onti titled 



REVIEW — TBOPICAL MEDICINE, ETC. 209 



inoculations with the parasite. The drug can be given by the mouth, intravenously or Trypanoso- 

 intra-peritoneally. The solution of arsenic should be prepared by boiling 1 gm. of miasis- 

 arsenious acid with 10 c.c. of normal caustic soda and subsequently adding 10 c.c. of 

 normal saline solution. The lethal dose per kilo of body weight is greater by about one-third 

 than the curative dose. Both doses ditfer for the different species of animals, but with care 

 there is no fear of poisoning. The arsenious acid acts directly upon the trypanosomes, not 

 through the medium of the leucocytes. The hyperleucocytosis which occurs is a secondary 

 phenomenon consequent on the destruction of the trypanosomes. It would seem that the 

 arsenic must be present in an adequate degree of concentration in the blood and tissue juices 

 if a complete effect is to be obtained. Otherwise, though the trypanosomes may disappear 

 from the circulation, they are not wholly destroyed, and relapse occurs. In vitro a dilution 

 of 1 in 200,000 is efficient. 



Magalhaes,! following up Kopke's work, has shown that certain drugs given by the mouth 

 or subcutaneous injection do not pass into the cerebro-spinal fluid, and so do not affect any 

 trypanosomes that may happen to be there. Iodine, potassium iodide and methylene blue 

 were employed both by the mouth and intramuscularly, but though later they were found 

 abundantly in the urine, they never penetrated the meninges. Apparently also atoxyl, 

 which has a real action on certain of the symptoms of the malady — notably on the fever and 

 on the disappearance of the trypanosomes from the blood and the glands — does not penetrate, 

 because, according to the autlior, the trj'panosomes always persist in the cerebro-spinal 

 fluid. The conclusion to be drawn from this, therefore, is that, in order to attack 

 them effectively in this position the drugs used must be introduced under the arachnoid 

 directly. 



Eeference may be made to a paper by Moore, Nierenstein and Todd,'- dealing with the 

 resistance shown by the parasites (notably T. hrucei, T. gamhietise and T. dimorphon) to 

 drugs, and the changes in virulence of the strains after they have escaped the drug action 

 and have reappeared in the blood. Atoxyl and acetylated atoxyl were used. 



Tsetse Flies. Of considerable importance and interest is the discovery by Carter' 

 of Glossina tachinoides (Westwood), in Southern Arabia, where it was found in several 

 different districts, but in no great numbers. It is said not to depend for its existence on 

 big game, because, excepting gazelle, nothing else frequents the belts of bush which 

 it haunts. Natives stated that it bit goats, donkeys, horses, dogs and men, but did not 

 attack camels or sheep. 



Stuhlman has published an exhaustive monograph dealing chiefly with Glossina fusca, 

 but G. tachinoides also receives some consideration. In a review** of his paper the following 

 points are noted : — 



1. Males greatly preponderated in his collections, which is strange, because, in the case of pupae, the proportion 

 was found to be equal. 2. A species of cocco-bacillus and a pink yeast organism were found to be common in the 

 digestive canal. 3. A hungry tsetse will absorb from 1"26 to '2'7 times its own weight of blood. 4. As regards 

 reproduction, it was found that a female laid eight larvae in three-and-a-half months, and that the pupa stage lasts 

 from thirty to sixty-five days. Twice females not certainly fecundated gave birth to larvae. 5. As regards the 

 influence of external conditions an average temperature of 23° to 26° C, with a maximum of 36° to 37° C., and a 

 minimum of 10° to 12° C, is necessary, combined with a degree of relative humidity ranging from 66 to 83 per 

 cent. 6. In nature it was found that from 3 to 14 per cent, of G. fusca contain trypanosomes within the 

 proboscis, while the digestive tube is infected in a much larger proportion. 7. Koch's description of the forms 

 of trypanosome found is confirmed — undiiferentiated forms being found in the hinder part of the intestine, 

 elongated forms in the proventriculus and oesophagus, and small forms chiefly in the proboscis. 8. Experimentally, 

 infection is most easily effected on the occasion of the fly's first meal after escaping fi'om the pupal case. 9. The 

 evidence is rather against the possibility of hereditary transmission. 10. What may have been a conjugation 

 of parasites was once observed in the proventriculus, and conjugation is said to be a necessary prelude to the 

 appearance of small forms in the proboscis, which constitute the agents of infection of vertebrates. Attempts to 

 infect the latter by means of injections of emulsion of the fluid obtained from the proventriculus uniformly failed. 



' Magalhaes, J. de (December Slst, 1906), " Troubles cerebelleux et bulbaires dans la Maladie du Sommeil." 

 Arch, de Eyg. et Path. Exot. (Lisbon), Vol. I., fasc. 2. 



^ Moore, B., Nierenstein, 51., and Todd, J. L. (July 1st, 1907), "Notes on the Effects of Therapeutic Agents 

 on Trvpanosomes in respect to («) Acquired Resistance of the Parasites to the Drug, and (6) Changes in Virulence 

 of the Strains after Escape from the Drug." Annals of Tropical Medicine and Parasitology, Series T. M., 

 Vol. II., No. 3. 



■■' Carter, R. M. (December 17th, 1906), " Tsetse Ply in Arabia." British Medical Journal, Vol. II. 



* Stuhlman, P. (March 2nd, 1908), "Contributions to our Knowledge of the Tsetse Plies." Journal of 

 Tropical Medicine and ffijgiene, Vol. XI. ; also in Bull, de Vlnstitut Pasteur (December 30th, 1907). 



* Article not consulted in the original. 



