Tolerability as assessed by the number of participants with clinical adverse experiences in the Vaccination and Follow-up Phases. A serious adverse event is any adverse event that results in death, is life threatening, results in a persistent or significant disability/incapacity, results in hospitalization or prolongs an existing hospitalization, is a congenital anomaly/birth defect, is a cancer, is an overdose, or is considered an "other important medical event" based on medical judgment.