Inactivated subunit or split influenza vaccine
ATC code: J07BB02 (Inactivated influenza vaccine)
Contains surface antigen fragments (hemagglutinin and neuraminidase) of currently circulating influenza strains A H1N1, H3N2, and B (Yamagata, Victoria) – usually quadrivalent composition per seasonal recommendation. Induces specific IgG antibodies without viral replication. Effectiveness 40-60% against lab-confirmed influenza depending on strain match and age.
First line
Annual seasonal influenza vaccination for individuals ≥6 months. Per CDC ACIP 2024 and SEMICYUC 2023, especially recommended for risk groups: age >65, children 6 months-5 years, pregnant, chronic lung/heart/kidney disease, immunocompromise, healthcare workers, contacts of infants. Dose 0.5 mL intramuscular (0.25 mL for some 6-35-month infants). Immunity by 2 weeks, lasts 4-6 months.
First line
Active maternal immunization against influenza. Per CDC ACIP 2024 and SEGO 2023, recommended in any trimester (preferably before seasonal peak). Reduces severe maternal disease and protects the infant for the first 6 months via transplacental antibodies.
First line
Influenza vaccine during breastfeeding. CDC ACIP 2024 and AEP CAV 2024 – fully compatible. Inactivated, no replication, anti-flu antibodies protect the infant via milk. Especially recommended if the infant is <6 months and cannot yet be vaccinated. Administer any trimester of pregnancy or immediately postpartum.
Opens the checker prefilled with this drug. Pick the second one from your regimen.
Recommended in any trimester per CDC ACIP and SEGO. Safe for mother and fetus.
Fully compatible. Inactivated, no replication. Antibodies protect the infant via milk. Hale L1.
Reference information, not a clinical decision. Discuss feeding pauses or changes with your physician or an IBCLC.
Inactivated influenza vaccine is evaluated for the following indications with varying evidence strength: Influenza prevention (evidence tier A), Vaccination during breastfeeding (evidence tier A), Maternal vaccination (evidence tier A). See the full indication matrix with dosing and citations above on this page.
Common side effects of Inactivated influenza vaccine (≥ 1 in 100): Injection-site pain (30-60%), Fatigue, Headache, Myalgia, Low-grade fever (5-10%). See the Safety section for uncommon and serious reactions.
FDA category B. Recommended in any trimester per CDC ACIP and SEGO. Safe for mother and fetus.
Fully compatible. Inactivated, no replication. Antibodies protect the infant via milk. Hale L1.
Inactivated influenza vaccine is contraindicated in: Anaphylaxis to previous dose or components; Severe egg allergy (for egg-based vaccines – relative, cell-based available); Acute febrile illness (defer). Full list in the Safety section.