Influvac Tetra (B/Phuket/3073/2013-Like Virus (B/Phuket/3073/2013, Wild Type), Influenza Virus B/Austria/1359417/202)

Influvac Tetra is a quadrivalent influenza vaccine indicated for the prevention of influenza caused by the included virus strains.

• Seasonal influenza: reduces the risk of infection from the four vaccine‑matched influenza viruses.
• Influenza B infection: provides specific protection against B/Phuket/3073/2013 and B/Austria/1359417/202 strains.
• High‑risk populations: helps lower the incidence of severe disease in elderly persons, young children, and individuals with chronic health conditions.

• Influvac Tetra contains inactivated influenza virus particles that stimulate the immune system to produce antibodies against the hemagglutinin and neuraminidase antigens of each included strain. The generated antibodies neutralize the virus upon exposure, providing active immunity that reduces infection and disease severity.

Common Side Effects

• Injection site pain: mild to moderate discomfort at the injection site.
• Redness or swelling: localized erythema or edema at the site.
• Low‑grade fever: transient temperature rise within 24‑48 hours.
• Headache: mild headache occurring shortly after vaccination.
• Myalgia: temporary muscle aches.

Serious or Rare Side Effects

• Anaphylaxis: severe allergic reaction requiring immediate medical attention.
• Guillain‑Barré syndrome: rare neurological disorder that may follow vaccination.
• Seizures: infrequent occurrence, especially in children with a history of febrile seizures.
• Severe allergic reaction: angioedema or bronchospasm.
• Thrombocytopenia: rare drop in platelet count.

Influvac Tetra should be administered only after evaluating the following considerations.

• Allergy to vaccine components: avoid if the patient has a known severe allergy to any ingredient.
• History of severe allergic reaction to previous influenza vaccines: defer administration.
• Acute febrile illness: postpone vaccination until recovery.
• Egg allergy: assess risk; vaccine may contain trace egg protein.
• Immunocompromised status: monitor response, as efficacy may be reduced.
• Store at 2‑8°C: keep refrigerated, protect from light, do not freeze or shake.

Vaccines may interact with other agents that affect immune response.

Major Interactions (Avoid)

• Live attenuated vaccines: avoid simultaneous administration to prevent interference.
• Immunoglobulin or blood products given within 3 days: may neutralize vaccine antigens.

Moderate Interactions (Monitor Closely)

• Antiviral medications (e.g., oseltamivir): may slightly reduce immunogenicity.
• Immunosuppressive therapy: monitor antibody response, may need revaccination.
• Corticosteroids at high dose: possible diminished vaccine efficacy.