RecruitingPhase 1Biological interventionA Phase 1 Randomized, Observer-blind, Placebo-controlled, Dose-escalation Clinical Trial to Evaluate the Safety and Immunogenicity of rVSV∆G-MARV-GP Vaccine in Adults in Good General HealthA Phase 1 Randomized, Observer Blind, Placebo-controlled, Dose-escalation and dose expansion Clinical Trial to Evaluate the Safety and Immunogenicity of rVSV∆G-MARV-GP Vaccine in Adults in Good General Health