Tamiami virus infection in mice and cotton rats.

Tamiami virus produces a lethal encephalitis in suckling mice, and the illness is mediated, at least in part, by cellular immunity. Infection of extraneural organs, including lymphoid organs, is limited. The same virus produces a widespread infection in its natural host, the cotton rat, but neither symptomatic illness nor cytopathology results. Since antibody is produced, as in the murine infection, suppression of cellular immunity to the virus may be responsible for the non-cytolytic infection. Lymphoid tissue is extensively infected in the cotton rat and a relationship between this lymphotropism and immunosuppression is suggested.