Trypanosoma rhodesiense (Stephens and Fantham) : a second species of African trypanosome producing sleeping sickness in man / by J.W.W. Stephens and H.B. Fantham.

  • John William Watson Stephens
Date:
[1912?]
Catalogue details

Licence: Public Domain Mark

Credit: Trypanosoma rhodesiense (Stephens and Fantham) : a second species of African trypanosome producing sleeping sickness in man / by J.W.W. Stephens and H.B. Fantham. Source: Wellcome Collection.

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    Action of Human Serum.—One c.cm. of human serum cured T. rhodesiense mice in 3 out of 4 cases; on TZ. gambiense mice there was no appreciable effect. Laveran and Nattan-Larrier have shown the same— namely, that human serums act on 7’. rhodesvense, but are quite without action on 7’. gambiense. (c) Trypanolytic Reactions.—The results got by Mesnil and Ringenbach are most demonstrative in the case of trypanolytic reactions. The serums of animals (man, monkey, and guinea-pig) infected with T. gambvense are trypanolytic for the homologous trypanosome—that is, T. gambiense—but have no action on the heterologous trypanosome—that is, 7’. rhodesiense. 4. Cross Immunity Hxperiments. (a) Mesnil and Ringenbach immunized a monkey (Macacus rhesus) against T. gambiense. It was inoculated with T. rhodesiense on June 7th, 1911; on June 27th trypanosomes appeared (the infection was slight) ; on July 4th it died. A control died in ten and a half days. (b) Laveran immunized a goat and mouse against T. gambiense ; when they had acquired a solid immunity they were inoculated with 7. rhodesiense. They became infected like the controls. (c) Laveran and Nattan-Larrier immunized a goat against T. brucei; it subsequently became infected with T. rhodestense. (qd) Laveran immunized a ram and a sheep against different strains of 7’. brucet. Inoculated with 7’. rhodest- ense they both acquired acute infections and died. Con- clusion: 7’. rhodesiense is not T. brucet. When the converse set of experiments is tried, namely, immunizing an animal against 7. rhodesiense, and then inoculating with T. gambiense, the difficulty immediately arises that it is impossible to immunize an animal against 7’. rhodesiense, owing to its virulence. But a partial and transitory immunity to 7’. rhodestense can be got by treat- ing the infected animal with drugs, such as arsenophenyl- glycin. The results, so far as they go, seem to show that an animal immunized against 7’. rhodesiense is immune not only to 7’. rhodesiense, but also to 7’. gambiense, a fact which, according to Mesnil and Leger, does not invalidate the specificity, but tends to show that the two trypano- somes are closely related. 5. Mode of Transmission. Although not regarding it as an absolute specific characteristic, it is interesting to note that according to Kinghorn and Yorke (1912): (1) T. rhodesiense is transmitted by Glossina morsitans, both in laboratory experiments and in nature. (2) That about 16 per cent. of the wild game examined in Northern Rhodesia is infected by 7’. rhodesiense.
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