Created by Sydney Price James
1923
Description:

'Colonel JAMES said: The specimens shown were collected during an enquiry into some of the clinical trials which are being made in mental hospitals in England of the method initiated a few years ago in Austria of treating general paralysis of the insane by inducing attacks of inoculated malaria. The enquiry is being undertaken by the Ministry of Health in collaboration with the Board of Control, primarily to ensure that all needful steps are taken to guard against the accidental spread of malaria, either in the hospitals concerned or to neighbouring populations. The first point to be ascertained in this enquiry is whether and to what degree a strain of parasite, which has been passed by direct inoculation from patient to patient through many human hosts, still remains infective to the anopheles mosquitoes of this country. There were many difficulties in carrying out this investigation during the winter, but in the result we have specimens of four insects showing sporozoites in the salivary glands and proboscis, and many specimens showing zygotes in the stomach wall. Under the particular conditions of our experiments from seventeen to twenty days elapsed between the date offeeding upon patients and the date when the finding of sporozoites in the salivary glands proved that the mosquitoes were infective to human beings.

The specimens of parasites in the blood of inoculated patients show some of the morphological characters of a strain which has been passed through about twenty human hosts. The strain was originally obtained from a case of benign tertian malaria contracted in the tropics. The slides show that in the inoculated case concerned the parasites were very numerous, and that the peripheral blood contained many large endothelioid macrophages and degenerated red-blood corpuscles: Typical male and female gametocytes are also shown, and a type of gametocyte which seems to resemble somewhat the forms described by THOMPSON and WOODCOCK on page 1,541 of the malaria article in BYAM and ARCHIBALD'S Practice of Medicine in the Tropics.'