Vaccinia infection of the nervous system in animals with normal and altered immune reaction.

The outcome of viral infection appears to be the result of a complex interplay of both viral and host factors. The virus-host cell relationship as well as the host's immune response are the major factors determining the type of infection and the expression of the disease. Demyelination disease appears to be rare complication of a systemic viral infection. The mayor factor in its expression is an altered response to the virus favoring the establishment of a noncytocidal abortive infection of the glial cells, which in turn induce a complex of potentially pathogenic immune mechanisms.