Mouse hydrocephalus and encephalitis following intracerebral infection with Newcastle disease vaccine viruses.

Hydrocephalus and encephalitis in 14-day-old mice was induced by an intracerebral inoculation of a high dose of live Newcastle disease vaccine viruses. The distended lateral ventricles occurred as a result of aqueduct stenosis superimposed on ciliary degeneration and destruction of ependymal cells. The brain virus titres were high on Days 3, 5 and 7 but never exceeded the titre of the original dose given. Positive serum haemagglutination-inhibition titres persisted throughout the experiment.