Susceptibility of the Chinese Stripted Hamster (Cricetulus Grisens) to Treponema pallidum

Abstract

Experiments to determine whether the Chinese hamster is susceptible to inoculation with Treponema pallidum have shown that organisms pathogenic for the rabbit may be recovered from certain tissues of this animal species. It would appear that there is dissemination of the organisms from the local focus of inoculation and presumably a multiplication of them occurs.

Hamsters were injected in one testicle with a tissue (orchitis) emulsion rich in spirochetes obtained from rabbits which had been inoculated with either the Nichol's strain or with a strain (P III) isolated from a patient in this hospital in 1926. At varying periods, the hamsters were killed by ether anesthesia and different tissues, emulsified with sterile normal saline were injected intratesticularly in normal rabbits. The rabbits were under observations approximately 3 months. In the case of those in which a clinical orchitis was not detected together with darkfield demonstration of spirochetes, the inoculated testicle and the popliteal lymph nodes were injected in a second set of rabbits; in a few instances, this procedure was repeated in a third set of rabbits.

The available results on the first generation of rabbit transfers may be summarized as follows: (1) In rabbits injected with the inoculated hamster testicle, 37, 64, and 138 days previously, a syphilitic orchitis developed in 2 to 3 weeks. (2) The inguinal lymph nodes of a hamster which was inoculated 64 days previously, induced a syphilitic orchitis in 2 rabbits in 7 and 9 weeks respectively; nodes from a hamster inoculated 138 days previously gave negative results in one rabbit. (3) Brain tissue of a hamster injected 138 days previously, induced a syphilitic orchitis in a rabbit in 43 days; negative results followed the injection of brain tissue of 2 hamsters injected 37 to 64 days previously.