A Study to Evaluate the Efficacy and Safety of Pimodivir in Combination With the Standard-of-Care Treatment in Adolescent, Adult, and Elderly Non-Hospitalized Participants With Influenza A Infection Who Are at Risk of Developing Complications

A Study to Explore the Antiviral Activity, Clinical Outcomes, Safety, Tolerability, and Pharmacokinetics of JNJ-53718678 at Two Dose Levels in Non-Hospitalized Adult Participants Infected With Respiratory Syncytial Virus