Annual Study for Collection of Serum Samples in Children and Older Adults Receiving the 2020-2021 Formulations of Fluzone Quadrivalent Vaccine and Fluzone High-Dose Quadrivalent Vaccine, Respectively

Inclusion criteria : * Aged 6 months to \<9 years or \>=65 years of age on the day of first study vaccination (study product administration). * For participants 6 to \<12 months of age, born at full term of pregnancy (\>=37 weeks) and with a birth weight \>=5.5 pound (lbs) (2.5 kilograms \[kg\]). * Informed consent form (ICF) was signed and dated by participants \>=65 years of age. * Assent form was signed and dated by participants 7 to \<9 years of age, and ICF was signed and dated by parent(s) or guardian(s) for participants 6 months to \< 9years of age. * Participants and parent/guardian (of participants 6 months to \<9 years of age) were able to attend all scheduled visits and to comply with all study procedures. Exclusion criteria: \- Participation at the time of study enrollment (or in the 30 days preceding the first study vaccination) or planned participation during the present study period in another clinical study investigating a vaccine, drug, medical device, or medical procedure. Note: Participants were considered eligible for enrollment if no intervention for the other study occurred within the 30 days prior to the first study vaccination and none are planned before the participant would complete safety surveillance for the present study. * Receipt of any vaccine in the 30 days preceding the first study vaccination, or planned receipt of any vaccine before Visit 2 for participants received 1 dose of influenza vaccine or Visit 3 for participants received 2 dos…