Primary Objective:
To demonstrate that high-dose quadrivalent influenza vaccine (QIV-HD) induces an immune response that is superior to the responses induced by standard-dose quadrivalent influenza vaccine (QIV-SD) for all 4 virus strains 28 days post-vaccination in participants 60 to 64 years of age and in participants 65 years of age and older.
Secondary Objective:
* Immunogenicity: To further describe the immune response induced by QIV-HD and QIV-SD in all participants by age group, in pooled age groups, and by vaccine group (QIV-HD; QIV-SD).
* Safety: To describe the safety profile of all participants by age group, in pooled age groups, and by vaccine group (QIV-HD; QIV-SD).