Induction of congenital hydrocephalus with mumps virus in rhesus monkeys

Rhesus monkey fetuses were inoculated intracerebrally with wild-type mumps virus near the beginning of the last third of the gestation period. Within three days after inoculation, mumps virus was isolated from many fetal tissues. Thirteen animals receiving virus were delivered at term. Five of these showed slight to severe hydrocephalus. Hydrocephalus was most prominent in the posterior horns of the lateral ventricles, but other lesions occurred at various levels of the ventricular system. Virus was isolated from three animals at one day of age (two months after inoculation). However, mumps virus was not recovered from one-month-old monkeys. The recovery of mumps virus from newborn rhesus monkeys two months after inoculation suggests that attempts should be made to document similar persistence of the virus in humans. Furthermore, this model indicates that mumps virus infection in humans may result in hydrocephalus.