Adverse Events;Full-length S-binding IgG levels;Local reactions (redness, swelling, and pain at the injection site) self-reported on e-diaries;Serious Adverse Events;Strain-specific HAI titers ; H3N2-neutralizing antibody titers (if H3N2-HAI titers cannot be obtained);Systemic events (fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain) self-reported on e-diaries

Adverse Events;Full-length S-binding IgG levels;Local reactions (redness, swelling, and pain at the injection site) self-reported on e-diaries;Serious Adverse Events;Strain-specific HAI titers ; H3N2-neutralizing antibody titers (if H3N2-HAI titers cannot be obtained);Systemic events (fever, fatigue, headache, chills, vomiting, diarrhea, new or worsened muscle pain, and new or worsened joint pain) self-reported on e-diaries