Influenza Vaccine, Inactivated, Trivalent

What it is and how it works

Contains inactivated split-virion or surface-antigen preparations of two influenza A strains (H1N1 and H3N2) and one influenza B strain, according to the annual WHO recommendation. It induces haemagglutination-inhibiting antibodies that protect against infection with matching strains.

Indications

Active immunisation against seasonal influenza, particularly in people at increased risk of complications (older adults, pregnant women, chronic disease) and health-care workers.

Dosage and administration (summary)

Adults and children from 9 years: a single 0.5 mL dose by intramuscular (or deep subcutaneous) injection each season; previously unvaccinated children aged 6 months to 8 years receive 2 doses at least 4 weeks apart.

Contraindications

Hypersensitivity to the active substances, excipients or residues (e.g. egg proteins, neomycin, formaldehyde) or a severe reaction to a previous dose; postpone in acute febrile illness.

Warnings and precautions

Appropriate treatment for anaphylaxis should be available. Antibody response may be reduced in immunosuppressed patients. Give with caution to patients with thrombocytopenia or coagulation disorders because of intramuscular injection; syncope may occur after vaccination.

Pregnancy

Recommended in any trimester of pregnancy to protect the mother and young infant.

Storage and supply

Store at 2–8 °C; do not freeze; protect from light.

Source: reference summary prepared from the EU SmPC/EPAR, BNF and WHO Model Formulary. The approved product information in Iran governs.