Immunity to C-type RNA viruses: antibody formation after natural or deliberate infection.

A combined virologic and immunologic study was done in mice that were either naturally or deliberately infected with C-type RNA viruses. In about 60% of B10. A mice, natural infection was accompanied by detectable anti-VEA antibodies in the serum. The absence of such antibodies was a reliable indicator of the absence of virus in B10 mice. Deliberately infected young adult B10 mice failed to eliminate the virus completely, despite high titers of anti-VEA antibodies. B10 mice exposed to B tropic viruses at birth made anti-VEA antibodies but failed to eliminate the virus. By contrast, some NIH Swiss mice exposed to N-tropic virus at birth made anti-VEA antibodies and eliminated the virus.