Influenza Vaccine Safety in Elderly Adults

Common Side Effects

• Local soreness at the injection site is the most frequent side effect, typically lasting up to 2 days, and is generally mild and not disabling, according to the American Thoracic Society 1, 2
• Systemic symptoms including fever, malaise, and myalgias may begin 6-12 hours after vaccination and typically last 1-2 days, occurring no more frequently than with placebo administration, as reported by the American College of Physicians 1, 2

Rare but Serious Adverse Events

• Rare immediate allergic reactions can occur in patients with egg hypersensitivity, as the vaccine is grown in eggs, as noted by the American Academy of Allergy, Asthma, and Immunology 1, 2
• Guillain-Barré syndrome was clearly associated only with the 1976 swine influenza vaccine and has not been associated with influenza vaccines since 1976, according to the Centers for Disease Control and Prevention 1, 2

Critical Safety Context

• The vaccine does not contain live virus and cannot lead to clinical influenza infection, as stated by the American Medical Association 1, 2
• The vaccine virus is inactivated, so it is impossible to develop influenza from vaccination, as confirmed by the Centers for Disease Control and Prevention 1, 3

Clinical Implications

• The side effect profile is exceptionally favorable, especially when weighed against the substantial mortality reduction (45-68%) and hospitalization reduction (50%) that vaccination provides in elderly adults, as reported by the American Geriatrics Society 1
• The enhanced protection of high-dose vaccines outweighs the minimal increase in mild local reactions in adults ≥65 years, as recommended by the American College of Cardiology 4, 5