Some critical remarks on Capt. Patton's Report on oriental sore / by C.M. Wenyon.

  • Charles Morley Wenyon
Date:
[1912]
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Licence: Public Domain Mark

Credit: Some critical remarks on Capt. Patton's Report on oriental sore / by C.M. Wenyon. Source: Wellcome Collection.

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    even in the ulcerating sores up to or at any rate nearly up to, the healing stage. Often a very careful search is necessary, and unless tissue is removed from the base of the ulcer, or preferably through an incision in the non- ulcerating part of the margin, the parasites may not be found. Sometimes, however, the ulcerating sore discharged a fluid not only teeming with bacteria of many kinds but also containing innumerable leishmania. Capt. Patton criticises the view that the house-fly may be responsible for the transmission of the disease, and for the period of one month he daily attempted to infect scratches on his hand by allowing flies to suck up the parasite- containing exudation from a sore and then to feed upon abrasions on his hand. No sore developed at these places ; so he thinks the fly is excluded as a carrier of the disease. He also points out that the people of Cambay are confident that the sore never commences in an abrasion, scratch, or open cut in the skin. Attempts were also made without success to produce a sore by placing some of the discharge containing parasites on the granulations of already existing sores of another kind. It is quite true that most usually the sore commences in healthy skin. Even if a cut or scratch were infected by the transference of a few parasites, the sore would only appear later after the wound had healed. This is the experience of all those who have practised direct inoculation by scarification; but to state that such wounds or sores never become infected requires further proof. I have the history of two Europeans who both contracted sores on the top of an abrasion. In one case an abrasion over the right cheek-bone resulting from a fall from a horse became infected, while in the other case an abrasion over the right shin-bone similarly developed into Oriental Sore. Capt. Patton’s feeding experiments with house-flies led to results similar to those obtained previously by Dr Row and the present writer. The parasites ingested could only be recovered up to six hours after feeding, after which they quickly degenerated and disappeared. There was no indication of a development into flagellate forms. Dr. Row has suggested that the house-fly may take up parasites and later pass them, still in a living condition, in the feeces, and that sores may be infected in this way. There is nothing against such a possibility, though it cannot be accepted till experimentally proved. Alvarez has sugested that fleas may infect dogs with Kala Azar by passing living leishmania in their faeces, and quite recently Noller has shown that forms of Trypanosoma lewist passed in the feeces by fleas are infective for rats, which naturally become infected with this trypanosome by licking up the forms deposited by the fleas on their skin. Capt. Patton, however, says that in order for the transmission to take place the fly must have a clean alimentary tract. Why this should be necessary is difficult to understand, for certainly the leishmania may live and develop to some extent in association with bacteria. Against the fly hypothesis the author quotes the fact that judging from people who become intected after only a short stay in Cambay, the sores are most commonly contracted, not in the fly season but in the cold weather. In Bagdad, however, I tound that though most sores make their first appearance at the beginning of the cool season, indicating that infection has probably taken place during the hot weather, they may appear at any time of the year. Experiments conducted with Pediculus vestimenti and Pediculus capitis gave negative results. , With Stegomyia sp. Capt. Patton conducted experiments ; but though these fed upon the sore, no parasites were discovered in them. With Stegomyza
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