Minutes of evidence taken by the Departmental Committee on Sleeping Sickness.
- Great Britain. Colonial Office. Committee on Sleeping Sickness.
- Date:
- 1914
Licence: Public Domain Mark
Credit: Minutes of evidence taken by the Departmental Committee on Sleeping Sickness. Source: Wellcome Collection.
17/346 (page 7)
![10 October 1913.] [ Continued. work. We keep the temperature and the humidity of the air all the year round and the number of days within which the flies become infective, the percentage which becomes infective, and so on. 103. About what difference in temperature do you get at the different seasons ’—In Nyasaland ? 104. Where you have been working in Nyasaland ? —I suppose an average mean temperature of perhaps 15 degrees difference. 105. What situations have youfound pups in P—As to morsitans we never find the pupe at all; one or two have been found but practically they are never found. 106. In the case of palpalis >—They are constantly _ at the edge of a lake or river and they have a pre- dilection for sandy shores, so that very often they are ge in large numbers on some suitable beach of sand. 107. I remember that in your Uganda work; you found the same thing in Nyasaland ?—We never found the pups of morsitans at all in Nyasaland; there are no palpalis in Nyasaland. 108. (Dr. Balfowr.) I only wish to ask you two questions and the first is an entomological one. Have you ever seen or heard of a tendency on the part of tsetse-flies, either morsitans or palpalis, to congregate on any special form of vegetable growth, such as tree- fungi, euphorbia, or plants of that nature P—No, I never saw anything of the sort. 109. We know that certain insects, Hemiptera or plant bugs, are known at the present time to acquire from plants, especially euphorbia, protozoal parasites which are allied morphologically in some respects to the trypanosomes, and one of those has been recently shown by a French observer to be patho- genic for small animals. Some such fact may possibly answer the question which the chairman put as regards the original origin of blood trypanosomes, and I wish to ask if you thought—TI do not say for a moment that at the present date any such thing may play a part in the infection; but is it possible that these leptomonas or herpetomonas may, owing to changes in environment, become pathogenic blood trypano- somes ?—Yes, I think that is a thing which may have happened in the past. “110. It would take a very long time for such a change to oceur P—Yes. 111. You do not think at the present time any pathogenic form of trypanosome would be likely to be found in such vegetable growths ?—I do not think so. 112. The only other question is with regard to Part VII. as regards other methods of dealing with the flies and destroying them: do you think it would be possible to devise any form of effective trap for trap- ping tsetse-flies P—I do not think so. . f 113. If such a trap could be devised do you think it could be used with advantage to proteet zones round villages and in palpalis country, at watering places and so on, as a subsidiary measure to what you have already proposed ?—I have never been able to think of anything which would be effective. 114. I take it any such trap would be better if it had some form of movement about it >—Yes, and life ; we tried blood in a gourd but it was a very great failure. 115. (Professor Newstead.) I think I will not venture to ask Sir David Bruce any question with regard to Glossina morsitans in Nyasaland, seeing that he and I have traversed the same country, but I should like to ask him a question with regard to the animal and fly prophylaxis. Do I gather you advocate three methods or three systems, first the clearing of big game from a given area; secondly, to clear that articular area ot all shade-giving vegetation; and thirdly, to fence that area with a fencing of some kind. Do I understand all these three experiments are to be conducted in one and the same area ?—The first thing is to put up the fence, and the next to clear out the game from the area and see what the effect of that is. Tf the fly still remain in numbers and infective, then try the third thing, that is, clear the scrub. 116. That is to say, it is just possible that after having driven out the game from that particular area tsetse-flies might still remain, and that then it might be found necessary to clear away the shade-giving 117. (Stir Stewart Stockman.) I think you probably gave the answer toa question I wanted to ask you, namely, to account for the absence of sleeping sick- ness in Zululand. May I take it the answer you gave just now was the explanation ora possible explana- tion P—There is one answer to that, and that is that in the fly area in Zululand, there are no natives, and there being no natives there can be no case of sleeping sick- ness among them. The reason why there are no natives is that the Zulu lives on his cattle; his cattle are his money and his life, he buys his wives with cattle, and everything is done with cattle; he will not live in a country where he cannot keep cattle, and therefore in the fly country there are no natives. The natives in this particular region here in Nyasaland are quite of a different class; they do not deal in cattle in that way so that this little area herejhas a population of some 20,000 inside it, which gives a better opportunity for the Trypanosoma brucei to get a chance, as it were at some particular man, 118. (Chairman.) When you say brucei you mean brucet vel rhodesiense—you do not distinguish between them ?—No. 119. (Sir Stewart Stockman.) Is it not rather curious there should be no case? I understand there has been no case, but I am not quite certain ?—I think it is very curious but I think it is quite possible that there may have been cases in these areas of this disease in man without its being noticed. I think it is only within a very few years that blood examinations have been made in these cases. J wrote in my summary of out in, that one of the most common diseases in the world was not recognised for hundreds of years; it was only recognised 13 years ago. Before that all these cases were returned as malaria. It has nothing to do with malaria. If the medical men had made proper blood examinations they could not have said it was . malaria. Soin the same way I think cases of T. bruce disease may have occurred, a few cases here and there, and that. they may have been called malaria and the man died and there was an end of it. 120. (Chairman.) Malta fever is the same thing ?— Yes; when I went to Malta in 1884 there was no such thing as Malta fever. It was all returned as remittent fever, or if it was a very serious case it was returned as enteric. Such is the habit in man of deceiving himself that I have seen a medical officer who had five years’ medical education looking at a piece of intestine, and saying, “ There is the enteric ulcer,” and I would look at it very closely and say, “I can see no ulcer there”; he says, ‘‘ Do you not see that ulcer there?” and I say, «“ No, I cannot see it,” and he goes and writes in his report that the intestine is markedly ulcerated. How these things happen I do not know, but that is the fact. 121. (Sir Stewart Stockman.) With regard to this suggested experiment it is the fact, is it not, that ina partial way we have already had something, not exactly an experiment, but something done following on the rinderpest in Africa ? Is it within your knowledge that after the rinderpest had swept away the game, certain parts of South Africa where stock farming was impos- sible before became possible for stock farming ?—Yes, I think so; again, that is one of those things you do not do by experiment, you have often to trust to hearsay evidence. When I was in Zululand in 1894, 1895, and 1896 (I left in 1897) the fly country was full of fly, and the rinderpest came in the next year and killed off most of the big game. When I came back from the war in 1902 there was some question (Mr. Austen here remembers it) as to the particular species of tsetse-fly which inhabited this par- ticular part of Zululand, and I was anxious to get some specimens so that Mr. Austen might see what they were. I wrote almost every year to the magistrate who lived on the top of the Ubombo hill overlooking the fly country asking him to send me specimens of the fly and he replied each year, ‘‘ There have been no flies here since the rinderpest passed through the country.” About 1908 I wrote again and got a box of flies which I .gave to Mr. Austen. Then the magistrate said,](https://iiif.wellcomecollection.org/image/b32178104_0017.jp2/full/800%2C/0/default.jpg)
