Influence of Host Factors on Neuroinvasiveness of Vesicular Stomatitis Virus Iii . Effect of Age and Pathway of Infection on the Character and Localization of Lesions in Tee Central Nervous System

The experimental data of the preceding investigations (I, 2) suggested tha t the failure of older animals, which readily succumb after intracerebral injection of the virus, to exhibit any clinical manifestations of central nervous system (CNS) involvement after peripheral inoculations was possibly due to the presence of certain barriers to the invasiveness of the virus, encountered at the site of inoculation when the intramuscular or intraocular routes were employed and within the CNS when the virus was given by way of the nose. The hypothesis of localized barriers developing with increasing age of the host depends to a great extent on evidence tha t the distribution or movement of this virus in the nervous system of mice occurs by different mechanisms after peripheral and intracerebral inoculations. The purpose of the present investigation was to determine whether a detailed study of the localization of lesions in the nervous systems of susceptible and resistant mice after different modes of inoculation could throw additional light on the movement of the virus and thus on the nature of the resistance of older animals.