This same method of infection of prostitutes has quite recently been brought to notice by Bernard.
It will be remembered that dourine, a trypanosome disease of horses, caused by T. equiperdum, is transmitted by the sexual act.
All observations however indicate that the spread of the disease is almost exclusively through the medium of the tsetse fly. Professor Lanfranchini was infected in his laboratory by a strain which was supposed to be Trypanosoma brucei.
Pathology
The chief pathological findings are the enlargements of the lymphatic glands. The dura mater may be adherent in places and the pia mater may show areas of thickening. The cerebro-spinal fluid is increased in amount. The pathological process is a chronic polyadenitis which is followed by a chronic inflammation of lymphatics of brain and spinal cord.
We have a meningo-encephalitis in which the most characteristic feature microscopically is a widespread perivascular infiltration of small round cells surrounding the vessels of the pia-arachnoid of both brain and cord. The process is most marked about vessels of pons and medulla. The nerve cells are but little affected other than those of the bulbar nuclei.
Fig. 29.—Temperature chart of trypanosome fever.