influenza a (h5n1) vaccine

Action and Spectrum

Actions and Spectrum: 

Actions: 

The influenza A (H5N1) vaccination prevents the recipient from contracting a serious illness in the event of virus exposure by stimulating the body’s immune system to create antibodies against the influenza A (H5N1) virus. The virus used to create the vaccine is cultivated in mammalian cells, purified, and inactivated to remove any potential for disease-causing.  

Hemagglutinins are sterile viral surface proteins (antigens) found in the influenza A (H5N1) vaccination that aid in the virus’s attachment to human respiratory cells and entry inside for replication. The immune system of the vaccinated individual possesses antibodies that recognize the virus based on its unique antigen and stop it from entering the cell to proliferate and infect more cells. 

Spectrum: 

The influenza A (H5N1) vaccine’s protective range is limited to the H5N1 subtype of the influenza A virus, genetic diversity, and immunity unique to a particular strain. 

Drug Interaction

Adverse Reaction

Frequency defined 

>10% 

Adults aged 18-64 years 

Myalgia (14%) 

Headache (25%) 

Injection site pain (64%) 

Malaise (22%) 

Fatigue (25%)  

Adults aged 65 years or older 

Headache (16%) 

Injection site pain (36%) 

Malaise (16%) 

Fatigue (20%)  

Children aged 6-17 years 

Myalgia (30%) 

Headache (22%) 

Injection site pain (68%) 

Malaise (25%) 

Fatigue (27%) 

Arthralgia (13%) 

Loss of appetite (14%) 

Nausea (13%) 

Infants and children aged 6 months through 5 years  

Fever >= 100.4 ºF (16%) 

Injection site tenderness (56%) 

Sleepiness (25%) 

Irritability (30%) 

Change in eating habits (18%)  

1-10%  

Adults aged 18-64 years 

Nausea (10%) 

Arthralgia (10%)  

Adults aged 65 years or older 

Arthralgia (10%)  

Children aged 6-17 years 

Injection site induration (2%) 

Nausea (1%) (Severe) 

Fever >= 100.4 ºF (4%) 

Injection site erythema (1%) 

Injection site pain (1%) (Severe) 

Malaise (1%) (Severe) 

Fatigue (1%) (Severe) 

Loss of appetite (1%) (Severe)  

Infants and children aged 6 months through 5 years  

Fever >= 100.4 ºF (2%) 

Injection site induration (1%) 

Injection site erythema (3%) 

Severe irritability (1%) 

Injection site tenderness (1%) 

Black Box Warning

Black Box Warning: 

The treating physician needs to maintain pharmacovigilance and keep a close eye on the patient. Children with weakened immune systems, such as those with cancer, HIV/AIDS, or certain medications, may not respond as well to the Influenza A (H5N1) vaccine. In order to improve protection, a healthcare provider may recommend adjusting the vaccination schedule or giving these individuals additional doses. 

The vaccination should be delayed if the patient has a fairly serious acute illness (with or without a fever of more than 101.3°F or 38.5°C). Healthcare professionals should carefully deliver a vaccine to a patient who is receiving additional vaccinations at the same time, taking into account any potential interactions and the time between immunizations. 

When choosing whether to administer the influenza A (H5N1) vaccination, careful consideration should be given to the potential hazards and benefits in the event that Guillain-Barré syndrome develops within six weeks of getting an earlier influenza vaccination. Alcohol Warning: When taking the influenza (H5N1) vaccine along with alcohol, exercise caution. 

Contraindication / Caution

Contraindication/Caution: 

Contraindications 

• Hypersensitivity/Anaphylaxis 

Cautions 

• Hypersensitivity reactions 
• Syncope 
• Guillain-barre syndrome 
• Drug interactions 
• Pregnancy 
• Breastfeeding 

Pregnancy / Lactation

Pregnancy consideration:  

No data is available regarding the administration of the drug during pregnancy. 

Breastfeeding warnings:  

No data is available regarding the excretion of drug in breast milk. 

Pregnancy category: 

Category A: well-controlled and satisfactory studies show no risk to the fetus in the first or later trimester. 

Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 

Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    

Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.    

Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.    

Category N: No data is available for the drug under this category. 

Pharmacology

Pharmacology: 

Hemagglutination-inhibition (HI) antibody titers have been employed as a gauge of influenza vaccine activity, however there is no evidence to link them to protection against H5N1 influenza. A protection against influenza sickness in as many as 50% of patients has been linked to antibody titers of ≥1:40 in several human challenge tests using different influenza viruses. 

Pharmacodynamics: 

The Influenza A (H5N1) vaccine interacts with the immune system, which may be a physiological mechanism contributing to its pharmacodynamic effects. Inactivated influenza A virus components are present in the vaccination. Immune-related cells identify these substances as foreign matter following infection, which sets off an immunological reaction. B cells help to produce virus-specific antibodies, whereas T cells aid in the development of immunological memory.

The immune system quickly identifies and eliminates the live influenza A virus when the body is exposed to it again, preventing the spread of illness. Protection against additional virus exposure is provided by this adaptive immune response. The effectiveness of the vaccine is dependent on the survival of the vaccination strains containing the influenza A virus variations that are currently in circulation. 

Pharmacokinetics: 

Parenteral administration of the influenza A (H5N1) vaccination is used. Pharmacokinetics, the typical process for pharmaceuticals, does not apply to it. It reduces the risk of infection, severe illness, and complications by stimulating the immune system to produce antibodies to protect against particular influenza A virus strains belonging to the Orthomyxoviridae RNA virus family, rather than going through the normal processes of absorption, distribution, metabolism, or elimination. 

Adminstartion

Administration: 

Parenteral administration of the influenza A (H5N1) vaccination is used. An injection (shot) of the H5N1 influenza virus vaccination is administered into a muscle. The H5N1 influenza virus vaccine is administered in two doses. 21 days following your initial dose, you receive your booster shot. It is unknown for children under six months of age.

For children six to eleven months of age, the vaccine is administered intramuscularly into the anterior lateral thigh; avoid injecting the gluteal region or any area where a significant nerve trunk may be present. For children over 12 months of age, the vaccine is administered directly into the deltoid muscle of the upper arm. 

Injectable vaccines must be administered concurrently, and separate syringes must be used for each shot at distinct locations. It’s crucial to keep an eye out for any indicators of acute allergic reactions for at least fifteen minutes after vaccination. 

The treating physician’s clinical judgment should be followed when determining the dosage and length of treatment. After mixing the H5N1 antigen and AS03 adjuvant, give the shot within 24 hours. Before administering the vaccine, let it sit at room temperature for at least fifteen minutes if it is kept chilled after mixing. 

Before each dose, fully combine the vaccine by inversion. When the solution and container allow, parenteral medication preparations should be visually scrutinized for discoloration and particle debris before being administered. It is not advisable to administer the vaccine if any of these symptoms are present. Both the injection of the vaccine and the removal of each dosage from the multi-dose vial need the use of a sterile syringe and needle (a 23-gauge is advised).

infants 6 months to 11 months old, the anterolateral thigh is the recommended injection location; for individuals 1 year of age and above, the deltoid muscle of the upper arm is the preferred injection site. It is not recommended to combine the influenza A (H5N1) virus monovalent vaccination with any other vaccine in the same vial or syringe. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: influenza A (H5N1) vaccine 

Pronounced: in-floo-EN-zuh eych-fahyv en-wuhn vak-seen 

Why do we use influenza A (H5N1) vaccine? 

The purpose of the influenza A (H5N1) vaccine is to provide protection against the H5N1 subtype of the influenza A virus, also referred to as avian influenza or bird flu. The influenza A (H5N1) vaccination prevents the recipient from contracting a serious illness in the event of virus exposure by stimulating the body’s immune system to create antibodies against the influenza A (H5N1) virus. The virus used to create the vaccine is cultivated in mammalian cells, purified, and inactivated to remove any potential for disease-causing.