Page:Transactions of the Royal Society of Tropical Medicine and Hygiene, volume 1.djvu/180

152

I FEEL that I owe an apology to this Society for again bringing before it the subject of filariasis, as one aspect of it was so recently and ably considered in the very interesting paper which was read by Dr. Low, and which went over some of the ground which I must necessarily cover; but my excuse must be that when I was asked to read a paper, I was unaware that a paper on the same subject was contemplated, and I had already been collecting material. If, then, I am unable to lay anything very new before you, I must crave your indulgence, and trust that the point of view from which I wish to approach it may be of sufficient interest to pardon any repetition, especially as I am inclined to take a different view of the relationship between filaria and disease from that which is generally held.

And, in the first place, it is necessary at once to exclude a number of filariae from the scope of this paper. Of Filaria demarquayi, F. ozzardi, F. perstans, and others, little is known as regards their life history, and no pathological condition is yet regarded as being associated with them. It was suggested, tentatively, that F. perstaiis might be the causal agent in sleeping sickness; we now know that it is due to a trypanosome. The disease known on the West Coast of Africa as craw-craw has also been associated with a filaria, but in my experience this is erroneous. In cases where there are filariae in the blood we