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Influenza Virus Vaccine, H5N1

Pronunciation: IN-floo-EN-za virus vaccine, H5N1
Class: Vaccine, viral

Trade Names

H5N1 Influenza Vaccine
- Injection, suspension 90 mcg HA of strain A/Vietnam/1203/2004 (H5N1, clade 1) per mL


Induce antibodies against the viral hemagglutinin in the vaccine, blocking viral attachment to human respiratory epithelial cells.

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Antibody against one influenza virus type or subtype confers little or no protection against viruses from other types or subtypes. Also, antibody to one antigenic variant of influenza viruses might not protect against a new antigenic variant of the same type or subtype.


Frequent development of antigenic variants through antigenic drift is the virological basis for seasonal epidemics and the reason for the usual change of 1 or more new strains in each year's influenza vaccine.

Indications and Usage

Active immunization of patients 18 to 64 yr of age at increased risk of exposure to the H5N1 influenza virus subtype contained in the vaccine.


None known.

Dosage and Administration

Adults 18 to 64 yr of age

IM Two 1 mL doses administered 21 to 35 days apart.

General Advice

  • Preferably inject in the lateral aspect of the deltoid muscle of the upper arm.
  • Between uses, return multiple-dose vial to the recommended storage conditions.
  • Do not mix another vaccine in the same syringe or vial.
  • Prior to administration of the vaccine, review the patient's prior immunization history for possible adverse reactions, which will allow assessment of benefits and risks.


Store at 35° to 46°F. Do not freeze. Protect from light.

Drug Interactions

Immunosuppressive therapies (eg, alkylating agents, antimetabolites, corticosteroids [in greater than physiologic doses], cytotoxic agents, irradiation)

Immune response to influenza virus vaccine, H5N1, may be reduced.

Laboratory Test Interactions

None well documented.

Adverse Reactions


Headache (36%); malaise (26%); myalgia (20%).


Nasal congestion, pharyngolaryngeal pain (5%); nasopharyngitis (4%).


Nausea (15%); diarrhea (6%).


Pain (74%); tenderness (70%); erythema/redness (20%); induration/swelling (15%).


Upper respiratory tract infection (5%).


Fever (11%).



Category C .




Safety and efficacy not established.


Safety and efficacy not established in patients 65 yr of age and older.


Product contains chicken and egg proteins. Base decision to administer to patients with known systemic hypersensitivity reactions of egg proteins or life-threatening reactions to previous influenza vaccinations on considerations of potential benefits and risks.

Guillain-Barré syndrome

If Guillain-Barré syndrome has occurred within 6 wk of receipt of prior influenza vaccine, base decision to give influenza virus vaccine, H5N1 on consideration of potential benefits and risks.

Impaired immune response

The expected immune response may not be obtained in immunocompromised persons, including those receiving immunosuppressive therapy.

Patient Information

  • Instruct patient or caregiver to report any serious adverse reactions to health care provider.

Copyright © 2009 Wolters Kluwer Health.