By peroral inoculation of JBE virus to the hamster, the infection could be established and the severity of infection seemed to depend upon the hamster's weight, lighter ones were more easy to be infected. The virus multiplied in the epithelium of intestine and then partly entered into the lymph stream, the mesenterial lymph nodules and thoracic duct and finally into blood circulation, and partly into portal vein, liver, hepatic vein and finally into general blood circulation. Thus, it gave rise to viremia. Virus given perorally got to the central nerves, and mostly through the choroid artery reached plexus chorioidea, as recognized by cellular infiltration in the plexus chorioides. JBE virus given perorally were excreted out in stool for 1 to 3 days. Following theadministration of JBE virus, the CF titer was not so raised as in cases of intravenous administration.
