ebola zaire vaccine

Action and Spectrum

Actions and Spectrum: 

• The ebola zaire vaccine is a viral vector that uses a harmless virus called the vesicular stomatitis virus (VSV) to deliver a gene that produces a surface protein from the ebola zaire virus. This protein stimulates an immune response that prepares the body to fight the ebola virus if it is encountered. 
• When the ebola zaire vaccine is administered, the VSV with the ebola protein gene enters the body’s cells and produces the ebola protein. The immune system recognizes the protein as foreign and mounts an immune response, producing antibodies that neutralize the ebola virus. 
• The vaccine is active against the ebola zaire virus, one of the deadliest strains. It is highly effective in preventing ebola virus disease in clinical trials, with a reported efficacy of up to 100%. 

Drug Interaction

Adverse Reaction

Frequency defined 

>10% 

Headache (36.9%) 

Muscle pain (32.5%) 

Joint pain (17.9%) 

Injection site redness (11.9%) 

Injection site pain (34-69.5%) 

Feverishness (34.3%) 

Fatigue (18.5%) 

Injection site swelling (16.5%)  

1-10% 

Joint pain/tenderness (7%) 

Rash (3.6-3.8%) 

Local reactions (e.g., redness, swelling) (1.8%) 

Nausea (8%) 

Arthritis (0.8-4.7%) 

Abnormal sweating (3.2%) 

Vesicular lesions (1.5%)  

<1% 

Joint swelling (0.4%) 

Arthropathy (joint redness/warmth) (0.6%) 

Joint stiffness (0.4%) 

Black Box Warning

Contraindication / Caution

Contraindications/caution: 

Contraindications: 

• Pregnancy: The vaccine is not recommended for pregnant women, as there is limited data on the vaccine’s safety in pregnant women. 
• Immunosuppression: The vaccine is not recommended for individuals with a weakened immune system, such as those undergoing chemotherapy or taking immunosuppressive medications, as their immune system may be unable to respond effectively. 
• Allergy to vaccine components: Individuals who have had a severe allergic reaction to any vaccine component, including the vesicular stomatitis virus (VSV) or any other ingredient, should not receive the vaccine. 
• Acute illness: Individuals with moderate or severe acute illnesses should delay vaccination until they recover. 
• Age: The vaccine is not recommended for children under one year of age, as there is limited data on the safety and effectiveness of the vaccine in this age group 

Caution: 

• Previous history of Guillain-Barre syndrome (GBS): Individuals who have had GBS in the past may be at an increased risk of developing the syndrome again after receiving the vaccine. Therefore, the vaccine should be given cautiously to these individuals and monitored closely for any signs or symptoms of GBS. 
• Bleeding disorders: Individuals with bleeding disorders, such as hemophilia, may be at an increased risk of bleeding after receiving the vaccine. Therefore, the vaccine should be given with caution to these individuals, and measures should be taken to minimize the risk of bleeding. 
• Allergies: Individuals with a history of allergies to other vaccines or injectable medications may be at an increased risk of developing an allergic reaction to the ebola zaire vaccine. Therefore, these individuals should be monitored closely for any signs or symptoms of an allergic reaction after receiving the vaccine. 
• Transmission of VSV: The vaccine uses a modified vesicular stomatitis virus (VSV) as a vector to deliver the ebola gene. There is a small risk of transmission of the VSV to close contacts of the vaccinated individual. Therefore, precautions should be taken to minimize the risk of transmission, such as covering the injection site with a bandage and practicing good hand hygiene. 

Pregnancy / Lactation

Pregnancy consideration: The vaccine is not recommended for pregnant women, as there is limited data on the vaccine’s safety in pregnant women. 

Lactation: Excretion of the drug in human breast milk is known 

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: There is no data available for the drug under this category 

Pharmacology

Pharmacology: 

• The ebola zaire vaccine is a viral vector that uses a harmless virus, called the vesicular stomatitis virus (VSV), to deliver a gene that produces a surface protein from the ebola zaire virus. The VSV used in the vaccine has been genetically modified so that it cannot cause disease in humans. 

• The ebola protein produced by the vaccine stimulates an immune response that prepares the body to fight the ebola virus if it is encountered. When the vaccine is administered, the VSV with the ebola protein gene enters the body’s cells and produces the ebola protein. The immune system recognizes the protein as foreign and mounts an immune response, producing antibodies that neutralize the ebola virus. 

• The ebola zaire vaccine is administered as a single dose by injection into the muscle. It is highly effective in preventing ebola virus disease in clinical trials, with a reported efficacy of up to 100%. 

• The vaccine has a short half-life, meaning it does not remain in the body for an extended period. Therefore, it is recommended that individuals receive the vaccine well in advance of potential exposure to the ebola virus. 

Pharmacodynamics: 

• The pharmacodynamics of the ebola zaire vaccine is related to its ability to stimulate an immune response that prepares the body to fight the ebola virus. The vaccine uses a viral vector, the vesicular stomatitis virus (VSV), to deliver a gene that produces a surface protein from the ebola zaire virus. This surface protein is similar to the protein found on the surface of the ebola virus. When the vaccine is administered, it stimulates the immune system to produce antibodies to neutralize the ebola virus. 

• The immune response to the vaccine begins within hours of administration, as the VSV with the ebola protein gene enters the body’s cells and begins to produce the ebola protein. The immune system recognizes the protein as foreign and mounts an immune response, producing antibodies that recognize and neutralize the ebola virus. 

• The immune response to the vaccine is long-lasting, and the antibodies produced can persist in the body for several years. This provides long-term protection against the ebola virus, although it is not yet clear how long the protection will last. 

• The pharmacodynamics of the ebola zaire vaccine has been studied extensively in clinical trials, where it is highly effective in preventing ebola virus disease. The vaccine has also been shown to be safe, with a low incidence of adverse events reported in clinical trials and real-world use. 

Pharmacokinetics: 

Absorption 

The vaccine is administered by injection into the muscle, and the viral vector carrying the ebola protein gene enters the body’s cells, producing the protein.  

Distribution 

The viral vector used in the vaccine has been modified to ensure that it does not cause disease, and it remains within the muscle cells where it was injected. It does not spread throughout the body and is not found in the blood or other tissues.  

Metabolism 

The viral vector used in the vaccine is metabolized within the muscle cells where it was injected, and the immune system recognizes the ebola protein produced by the gene as foreign.  

Elimination and Excretion 

The viral vector used in the vaccine is broken down and eliminated from the muscle cells within a few days of administration. The ebola protein the gene produces stimulates an immune response that can persist in the body for several years. 

Adminstartion

Administration: 

The ebola zaire vaccine is administered by injection into the muscle, usually in the upper arm. The vaccine is given as a single dose, taking 10-15 minutes to administer. 

Before administering the vaccine, the healthcare provider will ask about any medical conditions or allergies and provide information about the vaccine and its potential side effects.

The vaccine is usually administered in a healthcare setting, such as a clinic or hospital, under the supervision of a healthcare professional. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: ebola zaire vaccine 

Why do we use ebola zaire vaccine? 

The ebola zaire vaccine primarily prevents ebola virus disease, particularly in individuals at high risk of exposure to the virus. This includes healthcare workers, laboratory personnel, and individuals who may come into contact with the bodily fluids of ebola virus patients, such as family members or caregivers. 

The vaccine is highly effective in preventing ebola virus disease. It has been used in outbreak response efforts in several countries, including the Democratic Republic of Congo, Guinea, and Sierra Leone. The vaccine is also recommended for individuals traveling to areas where ebola virus outbreaks have occurred, particularly in regions of Africa where the virus is endemic.