Administration of an Attenuated Type I Poliomyelitis Virus to Human Subjects

Abstract
Two human subjects who had no antibodies against type I poliomyelitis virus were fed a mouse adapted attenuated type I virus. No clinical signs of illness resulted and no viremia was observed. Virus was excreted in the stools and specific blood circulating antibodies developed. One human subject was fed a mixture of the same type I strain and of an attenuated type II strain (Tn strain which in previous expts. was fed to a large number of subjects). Circulating antibodies developed against both types of poliomyelitis virus.