Does the Virus of Poliomyelitis Survive in the Monkey Testicle? ∗

Abstract

Among the points of major interest in experimental poliomyelitis is the question as to how long the virus is capable of surviving in different organs. Such data not only furnish information which is helpful in studying the factors responsible for selective tissue susceptibility, but may also add to our knowledge concerning the mode of invasion in the disease. From this viewpoint, the testicle has assumed particular prominence in practically all neurotropic virus diseases. It may either serve as portal of entry from which a generalized infection takes its beginning, or, more particularly, offer excellent ground for the development of a circumscript local lesion (herpes, vaccinia). It appears that infection by the testicular route so far has not been attempted in experimental poliomyelitis, save for the recent work of Thompson, 1 who reported his inability to infect rabbits by intratesticular injection with monkey virus. In these experiments it was also found that the virus does not survive for a period of even 24 hours in the rabbit testicle, as determined by subsequent transfer to the monkey.

We considered it important to extend these experiments to a study of the capacity of the testicle of a susceptible animal, i.e., the monkey, to serve either as a portal of entry for the disease or as a suitable living culture medium for the infectious agent. These experiments moreover afforded an opportunity to determine whether intratesticular injection of virus conveyed any active, generalized immunity to the monkey.

A total of 8 Rhesus monkeys, in several experiments, were injected intratesticularly with poliomyelitis passage virus (Aycock strain), the animals receiving doses of 0.5-1. cc. of a 20% monkey virus cord emulsion into each testicle. The virulence of the virus in each case was confirmed by parallel intracerebral inoculation of a control monkey with the same cord emulsion.