Properties of an encephalitogenic canine parainfluenza virus.

An isolate of canine parainfluenza (CPI) virus from the cerebrospinal fluid of a dog with neurological dysfunction was characterized in vitro in comparison to a prototype strain of CPI virus, D008. The virus, designated 78-238 was found to be antigenically related to CPI virus (Manhatten strain) and simian virus 5 (SV5), but not to mumps virus (Enders strain). Ultrastructural observation of gradient-purified 78-238 virus revealed enveloped pleomorphic virions with helical nucleocapsid symmetry. Preliminary pathological studies indicated that 78-238 virus was encephalitogenic for gnotobiotic dogs when inoculated by the intracerebral route.