Prevention of syphilis in Macacus Rhesus by atoxyl

Abstract

The drug atoxyl has been employed successfully in causing the rapid disappearance of syphilitic lesions in human beings and in preventing the development of the specific inoculation eye lesions in rabbits. Metchnikoff reported recently that the same drug would prevent the development of the specific lesion in monkeys even if administered some days after the inoculation. The experiment which I wish to report was made upon five Macac monkeys. They were all inoculated over both eyebrows with scrapings from a syphilitic papule of the tongue which had been shown by the dark field illumination microscope to be rich in living Spirocheta pallida. Two of the monkeys remained as controls and the other three received 0.15 gram atoxyl subcutaneously, one day, eight days and fifteen days respectively after the inoculation. Only the two controls developed specific lesions. Three months later two of the atoxyl-treated monkeys (one having died in the interim) and another control monkey were inoculated over the right eyebrow with virus from a primary syphilitic lesion rich in Spirocheta pallida. Within three weeks one of the atoxyl-treated monkeys and the control monkey developed specific lesions, showing the pallida, over the right eyebrow. This experiment is an example of the power which atoxyl possesses of suppressing the development of syphilitic lesions when given as late as fifteen days after inoculation with active virus, and indicates that this suppression is not attended with the production of a state of immunity to the virus.