VI. Experiments with the Trichomonads of Man and the Macaques
Published online by Cambridge University Press: 06 April 2009
It will be convenient at this point, before proceeding to a more general discussion of the findings, to summarize all the experiments recorded in the eight preceding subsections. Briefly the results are as follows:
(i) An attempt to infect a Macacus rhesus by feeding it with Trichomonas isolated from a monkey of the same species failed completely.
(ii) Four similar attempts to infect a Macacus sinicus with the same Trichomonas (from M. rhesus) were equally unsuccessful.
(iii) Two attempts to infect another M. sinicus by intra-intestinal inoculation with the same flagellate were likewise wholly negative.
(iv) One attempt to infect a man per os with the same strain of Trichomonas (from M. rhesus) did not succeed.
(v) A strain of Trichomonas from Man, when fed to a Macacus rhesus, produced no infection.
(vi) The same strain (T. hominis) fed to a Macacus sinicus likewise failed to infect.
(vii) A strain of Trichomonas from Macacus nemestrinus, however, when fed to M. rhesus, gave rise to a temporary infection lasting about a month.
(viii) This Trichomonas (from M. nemestrinus, after passage through M. rhesus) produced, nevertheless, a permanent infection—lasting 4½ years to date—when fed to a man.
(ix) The same strain of Trichomonas (from M. nemestrinus), after passage through M. rhesus and Man, when fed to a Macacus sinicus gave rise to an infection which endured for approximately 1½ months and then died out. But
(x) The very same Trichomonas (which was derived from M. nemestrinus, and which produced a temporary intestinal infection in M. rhesus and M. sinicus, and a permanent intestinal infection in Man) when introduced into the vagina of M. sinicus established itself enduringly as a typical “T. vaginalis.” The infection has now persisted for ome 3⅓ years.
(xi) The monkey (M. sinicus) in which a permanent vaginal infection with an intestinal Trichtomonas was established, has probably since reacquired no permanent intestinal infection—despite every natural opportunity for such reinfection.
(xii) No macaque suffered any harm whatsoever as a result of inoculation with any strain of Trichomonas–whether successful or unsuccessful.
(xiii) The one man successfully infected with Trichomonas (from M. nemestrinus) has likewise remained normal ever since.