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IIV

Inactivated

Influenza (Inactivated)

Manufacturer

Various (Sanofi, GSK, Seqirus)

Administration

Intramuscular (IM)

Site: Deltoid or Anterolateral thigh

Storage

Refrigerate at 2°C to 8°C. Do not freeze.

Schedule

1 dose annually

Indications

  • Annual prophylaxis against seasonal influenza.
  • Highly recommended for elderly, pregnant, and immunocompromised.

Target Ages:

Annually for everyone >= 6 months

Contraindications & Precautions

Contraindications

  • Severe allergic reaction to previous dose (Egg allergy is no longer a strict contraindication)

Precautions

  • History of Guillain-Barré Syndrome within 6 weeks of a previous flu vaccine.

Side Effects

Common (Expected)

Injection site sorenessMild myalgiaLow-grade fever

Rare Adverse Events

  • Guillain-Barré Syndrome (estimated 1-2 cases per million)

Clinical Information

Effectiveness

Varies year-to-year (usually 40-60%) depending on strain match.

Patient Counseling

  • The vaccine cannot cause the flu because it is inactivated.
  • Protection takes about 2 weeks to develop.