Dosing and uses of Influenza H5N1 Vaccine (influenza virus vaccine (H5N1))
Adult dosage forms and strengths
injection, suspension hemagglutinin H5N1 strain
- 90mcg/mL
- Only to government agencies and for stockpiles
H5N1 Influenza (Avian Flu)
Indicated for active immunization of adults aged 18-64 years at increased risk of exposure to H5N1
2-dose immunization series
90 mcg (1 mL) IM once; administer second 1 mL dose 28 days later (range 21-35 days)
Dosing Considerations
Safety and efficacy not established for adults >64 years
Specific strain: A/Vietnam/1203/2004
Also contains thimerosal, chicken protein, porcine gel, and egg protein
Pediatric dosage forms and strengths
Safety and efficacy not established
Influenza H5N1 Vaccine (influenza virus vaccine (H5N1)) adverse (side) effects
>10%
Headache (3-36%)
Malaise (22%)
Local pain (74%)
Local tenderness (70%)
Local erythema/redness (20%)
Induration/swelling (15%)
Myalgia (16%)
1-10%
Fever (6%)
Nausea (10%)
Diarrhea 6%)
Nasopharyngitis (2%)
Upper respiratory infection (2%)
Nasal congestion (1%)
Warnings
Contraindications
Documented hypersensitivity to vaccine, egg proteins, or other vaccine components
Cautions
Immune response may not be fully obtained in immunocompromised patients.
Use caution if Guillain-Barre syndrome has occurred within 6 weeks of prior influenza vaccine
Syncope accompanied by transient visual disturbances, tonic-clonic movements reported with injectable vaccines
Immunocompromised patients receiving chemo/radiation therapy or other immunosuppressive therapy may have reduced response to vaccine
Vaccine may not provide effective immunity in all patients
Pregnancy and lactation
Pregnancy category: C
Lactation: Unknown if distributed in human breastmilk; use with caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Influenza H5N1 Vaccine (influenza virus vaccine (H5N1))
Mechanism of action
Influenza vaccines induce antibodies against the viral HA in the vaccine, which then blocks viral attachment to human respiratory cells
Te mechanism of action of type A (H5N1) influenza virus is not well understood; promotes active immunity to avian influenza
Pharmacokinetics
In clinical trials, a 4-fold increase in antibody titers was seen in up to 58% of patients 28 days after second dose
Administration
IM Administration
Administer preferably in lateral aspect of deltoid muscle of upper arm
Do not inject gluteal region or areas where a major nerve trunk might be present
Needles less than 1-inch may not penetrate the muscle tissue; use needles at least 1-inch in size
Storage
Refrigerate at 2-8 C (35-46 F)
Do not Freeze (discard if frozen)
Protect from light
Do not use after expiration date.
