RECIPROCAL EFFECTS OF CONCOMITANT INFECTIONS : II. THE INFLUENCE OF VACCINAL IMMUNITY ON THE REACTION TO EXPERIMENTAL SYPHILIS.

Experiments are reported in which it was shown, first, that the effectiveness of the reaction to experimental syphilis was increased in rabbits immune to vaccine virus, the ensuing disease being less severe than in control animals. It was further shown that a comparable modification of the syphilitic reaction occurred in rabbits inoculated intratesticularly with a mixture of Treponema pallidum and vaccine virus, and it was suggested that this result was due to the influence of a vaccinal immunity and to the local effect of the vaccinal reaction. It was pointed out that the manner in which two concomitant experimental infections are induced is of significance in determining the character of the host's reaction.