Influvax Vaccine

Influvax Tetra Vaccine (Inactivated Influenza Vaccine, Quadrivalent) 0.5ml

Manufacturer: Incepta Pharmaceuticals Ltd.
Generic Name: Inactivated Influenza Vaccine (Split Virion), Quadrivalent (QIV)
Therapeutic Class: Vaccines / Influenza Prophylaxis
Presentation: 0.5ml pre-filled syringe
Price: ৳950.00 per pre-filled syringe

Indications

Influvax Tetra is indicated for active immunisation against influenza disease caused by influenza virus types A and B in:

• Adults and children aged 6 months and above
• Individuals at high risk of influenza complications: elderly (≥65 years), people with chronic respiratory disease (asthma, COPD), chronic cardiovascular disease, chronic kidney or liver disease, diabetes mellitus, immunocompromising conditions, and obesity
• Healthcare workers and caregivers of high-risk individuals
• Pregnant women (all trimesters)

Annual vaccination is recommended as influenza strains change each year and vaccine-induced immunity wanes over time.

Composition

Each 0.5ml pre-filled syringe contains split virion inactivated influenza antigens (haemagglutinin) from four strains recommended annually by the WHO:

• Influenza A (H1N1) strain — 15 mcg haemagglutinin
• Influenza A (H3N2) strain — 15 mcg haemagglutinin
• Influenza B (Victoria lineage) strain — 15 mcg haemagglutinin
• Influenza B (Yamagata lineage) strain — 15 mcg haemagglutinin

Strains are updated annually to match circulating virus variants per WHO guidance.

Mechanism of Action

Influvax Tetra is a split virion inactivated quadrivalent influenza vaccine. It stimulates the immune system to produce strain-specific antibodies, primarily against haemagglutinin (HA), which prevent the influenza virus from binding to host cell receptors. Protective antibody levels (haemagglutination inhibition titre ≥1:40) are typically achieved within 2–3 weeks of vaccination and confer protection against antigenically similar circulating influenza A and B strains for approximately one influenza season.

Dosage and Administration

Adults and children ≥9 years: One dose of 0.5ml, administered once per influenza season.

Children 6 months to 8 years (first-ever influenza vaccination): Two doses of 0.5ml, administered at least 4 weeks apart. In subsequent seasons, a single dose suffices.

Route: Intramuscular (IM) injection — preferred site is the deltoid muscle (adults and older children) or anterolateral thigh (infants and young children). Do not inject intravenously or subcutaneously.

Timing: Administer before the start of the influenza season (ideally October–November in the Northern Hemisphere, or as guided by local health authorities in Bangladesh).

Shake gently before use to obtain a homogeneous suspension. Inspect visually — do not use if the suspension appears abnormal or if the container is damaged.

Contraindications

• Known severe hypersensitivity (anaphylaxis) to any component of the vaccine, including egg proteins, neomycin, formaldehyde, or Triton X-100
• History of Guillain-Barré Syndrome within 6 weeks of a previous influenza vaccination (relative contraindication — assess risk vs. benefit)
• Febrile illness or acute infection — defer vaccination until recovery

Warnings and Precautions

• Administer only under medical supervision with adrenaline (1:1000) available for immediate treatment of rare anaphylactic reactions.
• The vaccine does not protect against all circulating influenza strains or other respiratory pathogens.
• Immunocompromised individuals may have a diminished immune response.
• Do not inject intravascularly — aspirate to confirm the needle is not in a blood vessel.
• Syncope (fainting) may occur after any injection; observe patients for 15 minutes post-vaccination.
• Contains residual egg protein (ovalbumin <1 mcg/dose); use with caution in individuals with egg allergy — consult an allergist if severe egg allergy is present.

Side Effects

Very common (≥1/10): Local reactions at injection site (pain, redness, swelling, induration); headache, malaise, myalgia, fatigue — typically mild and resolve within 1–2 days.

Common (≥1/100 to <1/10): Low-grade fever, arthralgia, chills, sweating.

Uncommon: Generalised skin reactions (urticaria, pruritus).

Rare: Neuralgia, paraesthesia, convulsions, thrombocytopaenia, anaphylaxis, vasculitis, Guillain-Barré Syndrome (extremely rare causal association).

Drug Interactions

• Immunosuppressants: May reduce the immune response to the vaccine.
• Other vaccines: Can be administered concomitantly with other inactivated or live vaccines at different injection sites using separate syringes, in accordance with national immunisation schedules.
• Warfarin/anticoagulants: IM injection carries risk of haematoma — apply firm pressure for at least 2 minutes post-injection; do not rub.

Use in Special Populations

Pregnancy: Safe and recommended throughout all trimesters of pregnancy. Annual influenza vaccination is recommended for all pregnant women by WHO and national immunisation programmes.

Lactation: Can be used safely during breastfeeding. Maternal antibodies may be transferred to the infant through breast milk.

Elderly (≥65 years): High-priority group for annual vaccination due to higher risk of influenza complications. Immune response may be lower than in younger adults; vaccination is nevertheless strongly recommended.

Paediatrics: Safe for children aged 6 months and above at the approved dose.

Storage

Store at 2°C to 8°C (refrigerated). Do not freeze — freezing destroys potency. Protect from light. Once removed from refrigeration, use promptly. Keep out of reach of children. Do not use after the expiry date printed on the syringe label.

Pricing

Influvax Tetra 0.5ml pre-filled syringe: ৳950.00 per dose

Disclaimer: This product information is for reference purposes only and does not substitute professional medical advice, diagnosis, or treatment. Always consult a registered physician or qualified healthcare professional before taking any medication.