An African Green Monkey has been inoculated with the "BIKEN" strain of defective measles virus to establish an animal model for human subacute sclerosing panencephalitis (SSPE). Insufficient time has elapsed since this project was initiated to draw firm conclusions. If a suitable subhuman primate model of SSPE results from this work, it will be used to study the role of antibody and/or cellular immunity in the development of chronic measles infection and to develop improved regimens for the control and treatment of human SSPE.