AVAXIM Junior
Inactivated Hepatitis A Vaccine for Children (1-15 Years)
Quick Facts about AVAXIM Junior
Key Takeaways about AVAXIM Junior
- Highly effective pediatric vaccine: AVAXIM Junior produces seroconversion in over 99% of children within 14 days of the first dose
- Two-dose schedule for long-term protection: An initial dose followed by a booster at 6-36 months provides protection estimated at 20-40 years or potentially lifelong
- Well-tolerated in children: Most side effects are mild and self-limiting, with injection site pain being the most common reaction
- Can be co-administered with other vaccines: AVAXIM Junior can be given alongside routine childhood vaccinations without reducing efficacy
- Especially important for travel: Recommended for children traveling to countries with high or intermediate hepatitis A endemicity
What Is AVAXIM Junior and What Is It Used For?
AVAXIM Junior is an inactivated hepatitis A vaccine designed for children aged 1 to 15 years. It contains inactivated hepatitis A virus (GBM strain) grown on human diploid cells and is used to provide active immunization against hepatitis A, a viral infection that primarily affects the liver.
Hepatitis A is a highly contagious liver infection caused by the hepatitis A virus (HAV). While the disease is often mild in young children, it can cause prolonged illness lasting several weeks to months in older children and adolescents. In rare cases, hepatitis A can lead to fulminant hepatic failure, particularly in individuals with pre-existing liver disease. The World Health Organization estimates that hepatitis A causes approximately 7,134 deaths annually worldwide, accounting for 0.5% of viral hepatitis-related mortality.
AVAXIM Junior works by presenting the immune system with inactivated (killed) hepatitis A virus particles. The body recognizes these viral antigens and mounts an immune response, producing antibodies that provide protection against future infection. Unlike live vaccines, inactivated vaccines cannot cause the disease they are designed to prevent, making AVAXIM Junior suitable for use in immunocompromised children under medical supervision.
The vaccine is manufactured by Sanofi Pasteur using the GBM strain of hepatitis A virus, which is propagated on MRC-5 human diploid cells and then inactivated with formaldehyde. Each 0.25 mL dose contains 80 units of inactivated hepatitis A virus antigen adsorbed onto aluminium hydroxide as an adjuvant, which enhances the immune response.
AVAXIM Junior is primarily indicated for children who are at increased risk of hepatitis A infection. This includes children traveling to or living in areas where hepatitis A is endemic (including parts of Africa, Asia, Central and South America, and Eastern Europe), children living in communities experiencing hepatitis A outbreaks, children with chronic liver disease (including those with hepatitis B or hepatitis C), children with hemophilia or other clotting factor disorders who may receive plasma-derived products, and children in close contact with infected individuals or known carriers.
AVAXIM Junior may also be used for post-exposure prophylaxis in unvaccinated children who have been in close contact with a confirmed hepatitis A case. When administered within 14 days of exposure, the vaccine can prevent or attenuate the disease. For children under 12 months of age or those who are immunocompromised, passive immunization with immunoglobulin may be preferred, as recommended by WHO and ACIP guidelines.
What Should You Know Before Taking AVAXIM Junior?
Before administering AVAXIM Junior, healthcare providers must assess for contraindications including severe allergic reactions to any vaccine component, acute febrile illness, and specific conditions that may require precautions. Parents and caregivers should disclose the child's complete medical history.
Contraindications
AVAXIM Junior should not be administered to children with a known history of severe allergic reaction (anaphylaxis) to a previous dose of any hepatitis A vaccine or to any component of the vaccine, including neomycin (used during the manufacturing process). The vaccine should also not be given to children younger than 12 months of age, as maternal antibodies may interfere with the immune response and the vaccine is not licensed for this age group.
Children with a confirmed severe allergy to formaldehyde should not receive the vaccine without specialist consultation, as trace amounts may be present from the inactivation process. Similarly, children with a documented severe allergy to 2-phenoxyethanol (used as a preservative) should be evaluated by an allergist before vaccination.
Warnings and Precautions
Vaccination should be postponed in children with moderate or severe acute illness, with or without fever. Minor illnesses such as mild upper respiratory infections are generally not a reason to delay vaccination. Healthcare providers should be equipped to manage anaphylaxis in the unlikely event of a severe allergic reaction following vaccination, and children should be observed for at least 15 minutes after injection.
AVAXIM Junior should be administered with caution in children with thrombocytopenia or any bleeding disorder, as intramuscular injections may cause bleeding at the injection site. In such cases, the vaccine may be given subcutaneously, although the intramuscular route is preferred for optimal immune response. Children receiving anticoagulant therapy should also be managed carefully.
The immune response to AVAXIM Junior may be reduced in children receiving immunosuppressive therapy, including high-dose corticosteroids, chemotherapy, or biological agents. Vaccination should ideally be scheduled before the start of immunosuppressive treatment or during a treatment-free interval. If this is not possible, the vaccine can still be given, but serological testing may be warranted to confirm seroconversion.
As with all injectable vaccines, AVAXIM Junior should not be administered intravenously, intradermally, or subcutaneously (unless intramuscular injection is contraindicated). Inadvertent intravascular injection must be avoided. The vaccine should be injected into the deltoid muscle of the upper arm in older children or the anterolateral thigh in toddlers.
Pregnancy and Breastfeeding
While AVAXIM Junior is intended for pediatric use (ages 1-15 years), it is important to note that there are limited data on the use of inactivated hepatitis A vaccines during pregnancy. If an adolescent who is pregnant requires hepatitis A vaccination, the adult formulation (AVAXIM 160U) should be considered in consultation with a healthcare provider. Inactivated vaccines are generally considered safe during pregnancy when clearly indicated, as they do not contain live virus.
There are no specific concerns regarding breastfeeding, as inactivated vaccines do not pose a risk to the nursing infant. Breastfeeding adolescents can receive hepatitis A vaccination without interrupting breastfeeding.
How Does AVAXIM Junior Interact with Other Drugs?
AVAXIM Junior can be safely co-administered with most routine childhood vaccines and does not have clinically significant interactions with common medications. However, immunosuppressive therapies may reduce the vaccine's effectiveness.
One of the practical advantages of AVAXIM Junior is its compatibility with other vaccines in the childhood immunization schedule. Clinical studies have demonstrated that AVAXIM Junior can be administered concurrently with a wide range of vaccines without clinically significant interference with the immune response to any of the vaccines involved.
When co-administered with other injectable vaccines, AVAXIM Junior must be given at a separate injection site using a separate syringe. The vaccines should not be mixed in the same syringe unless specifically approved for combination. The following table summarizes key interactions and co-administration data.
| Interacting Agent | Type | Effect | Recommendation |
|---|---|---|---|
| MMR vaccine | Vaccine co-administration | No reduction in immune response to either vaccine | Can be given simultaneously at different sites |
| DTaP / IPV / Hib vaccines | Vaccine co-administration | No clinically significant interaction | Can be given simultaneously at different sites |
| Hepatitis B vaccine | Vaccine co-administration | No interference; combined Hep A+B vaccines also available | Can be given simultaneously at different sites |
| Pneumococcal / Meningococcal vaccines | Vaccine co-administration | No reduction in antibody response | Can be given simultaneously at different sites |
| Immunoglobulin (IG) | Passive immunization | May reduce vaccine effectiveness if given simultaneously | Can be given concurrently at different sites; seroconversion rates may be lower but still protective |
| Immunosuppressive agents (corticosteroids, chemotherapy, biologics) | Drug interaction | Reduced immune response to vaccine | Vaccinate before starting therapy if possible; consider serological testing post-vaccination |
| Anticoagulants (warfarin, heparin) | Drug interaction | Increased bleeding risk at injection site | Use fine needle (23 gauge or smaller); apply firm pressure for 2+ minutes |
Major Interactions
The most clinically significant interaction is with immunosuppressive therapy. Children receiving high-dose systemic corticosteroids (equivalent to prednisone 2 mg/kg/day or more, or 20 mg/day for children weighing more than 10 kg, for 14 days or more), chemotherapy, or biological immunosuppressants (such as TNF-alpha inhibitors, rituximab, or other B-cell depleting agents) may have a significantly blunted immune response to AVAXIM Junior. In these children, vaccination should ideally occur at least 2 weeks before starting immunosuppressive therapy or at least 3 months after completing it, depending on the specific agent used.
Co-administration with human normal immunoglobulin (HNIG) may also attenuate the antibody response to the vaccine. When both passive and active immunization are required for post-exposure prophylaxis, they can be given simultaneously at separate injection sites. However, the resulting antibody titers may be lower than with vaccination alone, although they are generally still considered protective.
Minor Interactions
Standard over-the-counter medications such as paracetamol (acetaminophen) and ibuprofen do not affect the immune response to AVAXIM Junior and may be used to manage post-vaccination fever or injection site pain. Prophylactic use of antipyretics before vaccination is generally not recommended, as some studies suggest a potential modest reduction in antibody titers, although this remains debated.
Topical anesthetics such as EMLA cream (lidocaine-prilocaine) can be applied to the injection site before vaccination to reduce pain, particularly in needle-phobic children, without affecting vaccine efficacy.
What Is the Correct Dosage of AVAXIM Junior?
AVAXIM Junior is administered as a two-dose intramuscular injection schedule. The primary dose is a single 0.25 mL injection, followed by a booster dose of 0.25 mL given 6 to 36 months later, ensuring long-term protection for children aged 1 to 15 years.
Children (1-15 Years)
Primary Vaccination
Dose: 0.25 mL (80 U of inactivated hepatitis A virus)
Route: Intramuscular injection into the deltoid muscle (children aged 2 years and older) or the anterolateral thigh (toddlers aged 12-23 months)
Schedule: Single dose at a chosen date. Protection begins approximately 14 days after the first dose, with seroconversion rates exceeding 99% by day 28.
Booster Vaccination
Dose: 0.25 mL (80 U of inactivated hepatitis A virus)
Timing: 6 to 36 months after the primary dose (preferably 6-12 months for optimal long-term immunity)
Purpose: Ensures durable, long-term protection estimated at 20-40 years or potentially lifelong. The booster significantly increases antibody titers and establishes robust immunological memory.
| Age Group | Dose | Injection Site | Schedule |
|---|---|---|---|
| 12-23 months | 0.25 mL (80 U) | Anterolateral thigh | Dose 1 + booster at 6-36 months |
| 2-15 years | 0.25 mL (80 U) | Deltoid muscle (upper arm) | Dose 1 + booster at 6-36 months |
| 16+ years (transition to adult formulation) | 0.5 mL (160 U) – adult AVAXIM | Deltoid muscle | Dose 1 + booster at 6-36 months |
Adults
AVAXIM Junior is not indicated for individuals aged 16 years and older. For adolescents transitioning to adulthood and adults requiring hepatitis A vaccination, the adult formulation AVAXIM (160 U per 0.5 mL dose) should be used. If a child has received a first dose of AVAXIM Junior before their 16th birthday, the booster dose can be either AVAXIM Junior (if administered before the child turns 16) or AVAXIM adult formulation (if the booster is given at age 16 or older).
Elderly
AVAXIM Junior is a pediatric formulation and is not intended for use in elderly patients. Adults of all ages, including the elderly, should receive the adult formulation AVAXIM 160U. Elderly individuals may have a somewhat reduced immune response to hepatitis A vaccines, but vaccination remains effective and recommended for those at risk.
Missed Dose
If the booster dose is delayed beyond the recommended 6-36 month window, it should be administered as soon as possible. There is no need to restart the vaccination series. Studies have shown that even when the booster is given several years after the primary dose, a strong anamnestic (memory) immune response occurs, rapidly restoring protective antibody levels. The WHO and ACIP guidelines confirm that extended intervals between the primary and booster doses do not reduce the final level of protection achieved.
If there is uncertainty about whether a child has previously received the primary dose, revaccination with a full two-dose schedule is safe and can be administered without adverse consequences.
Overdose
Cases of overdose with AVAXIM Junior are extremely rare. In the unlikely event that more than the recommended 0.25 mL dose is administered, the child should be monitored for any increase in local reactions at the injection site or systemic adverse effects. No specific antidote is required. Clinical experience with inactivated vaccines suggests that inadvertent overdose does not cause serious adverse effects, although local reactions (pain, redness, swelling) may be more pronounced.
If the adult formulation (AVAXIM 160U, 0.5 mL) is accidentally administered to a child instead of the pediatric formulation, the child should be monitored but no specific action is required, as the adult dose contains twice the antigen content but is not expected to cause harm.
What Are the Side Effects of AVAXIM Junior?
AVAXIM Junior is generally well-tolerated in children. The most common side effects are injection site reactions (pain, redness, swelling) and mild systemic symptoms such as decreased appetite, irritability, and low-grade fever. Serious adverse events are very rare.
Like all vaccines, AVAXIM Junior can cause side effects, although not every child will experience them. The safety profile of AVAXIM Junior has been extensively studied in clinical trials involving thousands of children worldwide. Most side effects are mild, transient, and resolve within 1 to 3 days without specific treatment. The following frequency classification is based on clinical trial data and post-marketing surveillance.
Very Common
Affects more than 1 in 10 children (>10%)
- Injection site pain, tenderness, or soreness
- Injection site redness (erythema)
- Injection site swelling or induration
- Irritability or fussiness (in younger children)
- Decreased appetite
- Drowsiness or sleepiness
Common
Affects 1 in 10 to 1 in 100 children (1-10%)
- Headache
- Fever (38.0-39.0°C / 100.4-102.2°F)
- Gastrointestinal disturbances (nausea, vomiting, diarrhea)
- Muscle pain (myalgia)
- Joint pain (arthralgia)
- Fatigue or malaise
Uncommon
Affects 1 in 100 to 1 in 1,000 children (0.1-1%)
- High fever (>39.0°C / >102.2°F)
- Skin rash or urticaria (hives)
- Injection site nodule or lump
- Abdominal pain
- Crying (prolonged, inconsolable in infants)
Rare / Very Rare
Affects fewer than 1 in 1,000 children (<0.1%)
- Anaphylaxis or severe allergic reaction
- Serum sickness-like reaction
- Vasculitis (inflammation of blood vessels)
- Paresthesia (tingling or numbness)
- Convulsions (febrile seizures)
- Lymphadenopathy (swollen lymph nodes)
Injection site reactions are the most frequently reported side effects and typically begin within hours of vaccination, peaking at 24-48 hours and resolving by 72 hours. Pain at the injection site can be managed with the application of a cool compress and the use of age-appropriate analgesics such as paracetamol (acetaminophen) or ibuprofen if needed.
Fever after vaccination is usually low-grade (below 39°C) and self-limiting, typically resolving within 24-48 hours. Parents should be advised to monitor their child's temperature and administer antipyretic medication if the child appears uncomfortable. Children should be kept well-hydrated during this period.
Seek emergency medical care if your child develops signs of a severe allergic reaction (anaphylaxis) after vaccination, including difficulty breathing, swelling of the face or throat, rapid heartbeat, severe skin rash or hives, dizziness, or collapse. Although extremely rare, anaphylaxis is a medical emergency. Healthcare settings should always have appropriate equipment and medications (including epinephrine) readily available when administering vaccines.
Long-term safety data from post-marketing surveillance over more than two decades have confirmed the favorable safety profile of inactivated hepatitis A vaccines in children. No increased risk of autoimmune conditions, neurological disorders, or other serious long-term adverse effects has been identified in epidemiological studies. The WHO, EMA, and regulatory agencies worldwide continue to affirm the safety of hepatitis A vaccination in children.
How Should You Store AVAXIM Junior?
AVAXIM Junior must be stored in a refrigerator at 2°C to 8°C (36°F to 46°F), protected from light. Do not freeze. The vaccine should be discarded if the cold chain has been compromised or if the expiration date has passed.
Proper storage is essential to maintain the potency and safety of AVAXIM Junior. The vaccine must be kept in a refrigerator at a temperature between 2°C and 8°C (36°F to 46°F) at all times. It should be stored in the original packaging to protect it from light, as exposure to ultraviolet light can degrade the vaccine antigens over time.
Do not freeze AVAXIM Junior. Freezing irreversibly damages the aluminium hydroxide adjuvant, causing it to form aggregates that reduce the vaccine's immunogenicity and may increase the risk of injection site reactions. If there is any suspicion that the vaccine has been frozen, it must be discarded and not administered. The "shake test" can be used to check whether a vaccine has been frozen: a properly stored vaccine will form a uniform, slightly turbid suspension upon shaking, while a previously frozen vaccine may show visible floccules or granules that settle rapidly.
Once removed from refrigeration, the vaccine should be used promptly. If stored at room temperature (up to 25°C), the vaccine can be used within a limited time frame as specified by the manufacturer, typically within a few hours. However, it is best practice to minimize time outside of cold storage.
Before administration, the pre-filled syringe should be shaken well to ensure a uniform suspension. The vaccine should appear as a whitish, turbid suspension. Do not use the vaccine if it contains visible particles, appears discolored, or if the syringe or packaging appears damaged. Check the expiration date on the label before use, and discard any expired vaccine.
Parents and caregivers receiving the vaccine for travel purposes should be aware that AVAXIM Junior must be kept refrigerated during transport. Insulated cool bags with ice packs (ensuring the vaccine does not come into direct contact with ice packs to avoid freezing) can be used for short transport periods, but the vaccine should be transferred to a refrigerator as soon as possible.
What Does AVAXIM Junior Contain?
AVAXIM Junior contains inactivated hepatitis A virus (GBM strain) as the active ingredient, adsorbed onto aluminium hydroxide as an adjuvant, with 2-phenoxyethanol as a preservative and trace amounts of formaldehyde and neomycin from the manufacturing process.
Understanding the complete composition of AVAXIM Junior is important for healthcare providers assessing children for potential allergies or contraindications. The full list of ingredients is as follows:
Active substance:
- Inactivated hepatitis A virus (GBM strain), propagated on MRC-5 human diploid cells – 80 U per 0.25 mL dose
Adjuvant:
- Aluminium hydroxide, hydrated (expressed as aluminium) – 0.15 mg Al³⁺ per dose. The adjuvant enhances the immune response by creating a depot effect at the injection site, allowing prolonged antigen presentation to immune cells.
Preservative:
- 2-Phenoxyethanol – 2.5 μL per dose. This serves as a preservative to prevent microbial contamination.
Other excipients:
- Medium 199 Hanks (a complex mixture of amino acids, mineral salts, vitamins, and other components) without phenol red – used as the diluent and stabilizer
- Water for injections – quantity sufficient to 0.25 mL
- Hydrochloric acid or sodium hydroxide – for pH adjustment
Residual substances from manufacturing:
- Formaldehyde – trace amounts (≤12.5 μg per dose), used during the inactivation process
- Neomycin – trace amounts, an aminoglycoside antibiotic used during cell culture to prevent bacterial contamination
AVAXIM Junior does not contain any egg-derived proteins (as the virus is grown on human diploid cells, not embryonated eggs), thiomersal (mercury-based preservative), gelatin, latex (the syringe tip cap does not contain natural rubber latex in current formulations), or any animal-derived components other than the bovine-derived components that may be present in trace amounts in the cell culture medium.
The pre-filled syringe is made of Type I borosilicate glass, with a bromobutyl rubber plunger stopper. The syringe is provided with an attached needle or without a needle, depending on the market and packaging format. Healthcare providers should check the specific product packaging for their region.
Frequently Asked Questions about AVAXIM Junior
AVAXIM Junior is an inactivated hepatitis A vaccine specifically designed for children aged 1 to 15 years. It is used for active immunization to prevent hepatitis A virus infection. The vaccine is particularly recommended for children traveling to countries where hepatitis A is common, children living in communities experiencing outbreaks, children with chronic liver disease, and children in other high-risk groups as identified by public health authorities.
Your child needs two doses of AVAXIM Junior for complete, long-term protection. The first dose is given at a chosen date and provides initial protection within about 14 days. The second dose (booster) should be given 6 to 36 months after the first dose. This two-dose schedule provides protection that is estimated to last 20 to 40 years or potentially a lifetime. If the booster is delayed, there is no need to start over – simply give the second dose as soon as possible.
Yes, AVAXIM Junior can be safely given at the same time as most other childhood vaccines, including MMR, DTaP, polio (IPV), Hib, hepatitis B, pneumococcal, and meningococcal vaccines. When given alongside other injections, a different injection site should be used for each vaccine. Clinical studies have confirmed that co-administration does not reduce the effectiveness of any of the vaccines or increase the risk of side effects.
Low-grade fever (below 39°C / 102.2°F) is a common side effect that usually resolves within 24-48 hours. Keep your child well-hydrated and lightly dressed. You may give age-appropriate doses of paracetamol (acetaminophen) or ibuprofen if your child appears uncomfortable. If the fever exceeds 39°C (102.2°F), persists for more than 48 hours, or is accompanied by unusual symptoms such as severe lethargy, persistent vomiting, or a rash, contact your healthcare provider promptly.
Yes, AVAXIM Junior is safe for children with egg allergy. The hepatitis A virus in this vaccine is grown on MRC-5 human diploid cells, not in eggs. Therefore, the vaccine does not contain egg proteins and egg allergy is not a contraindication. However, children with a known severe allergy to neomycin (an antibiotic present in trace amounts) or formaldehyde should discuss this with their healthcare provider before vaccination.
After the complete two-dose series, protection against hepatitis A is estimated to last at least 20 to 40 years and may be lifelong. Long-term follow-up studies and mathematical modeling have shown that antibody levels remain well above the protective threshold for decades after vaccination. Currently, no additional booster doses are recommended beyond the initial two-dose schedule for individuals with a healthy immune system.
References
- World Health Organization (WHO). Hepatitis A vaccines: WHO position paper – October 2022. Weekly Epidemiological Record. 2022;97(40):493-512. Available at: who.int
- Advisory Committee on Immunization Practices (ACIP). Prevention of Hepatitis A Virus Infection in the United States: Recommendations of the Advisory Committee on Immunization Practices, 2020. MMWR Recomm Rep. 2020;69(5):1-38.
- European Medicines Agency (EMA). AVAXIM Summary of Product Characteristics. Updated 2024. Available at: ema.europa.eu
- Ott JJ, Irving G, Wiersma ST. Long-term protective effects of hepatitis A vaccines: A systematic review. Vaccine. 2012;31(1):3-11. doi:10.1016/j.vaccine.2012.09.073
- Innis BL, Snitbhan R, Kunasol P, et al. Protection against hepatitis A by an inactivated vaccine. JAMA. 1994;271(17):1328-1334.
- Vidor E, Dumas R, Bailleux F, et al. Immunogenicity and safety of the pediatric formulation of an inactivated hepatitis A vaccine in children aged 1-15 years. Pediatr Infect Dis J. 2003;22(2):102-108.
- Centers for Disease Control and Prevention (CDC). Epidemiology and Prevention of Vaccine-Preventable Diseases: Hepatitis A. The Pink Book, 14th Edition, 2021.
- Plotkin SA, Orenstein WA, Offit PA, Edwards KM. Plotkin's Vaccines. 7th ed. Elsevier; 2018. Chapter: Hepatitis A Vaccine.
- Fiore AE, Wasley A, Bell BP. Prevention of hepatitis A through active or passive immunization: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2006;55(RR-7):1-23.
- Dagan R, Amir J, Mijalovsky A, et al. Immunization against hepatitis A in the first year of life: priming despite the presence of maternal antibody. Pediatr Infect Dis J. 2000;19(11):1045-1052.
About the Medical Editorial Team
This article has been written and medically reviewed by the iMedic Medical Editorial Team, comprising licensed specialist physicians in clinical pharmacology, pediatrics, and immunization. Our content follows international medical guidelines from WHO, EMA, CDC, and ACIP, and is graded according to the GRADE evidence framework.
All medical claims are supported by peer-reviewed research and international guidelines. Evidence level: 1A – based on systematic reviews and meta-analyses of randomized controlled trials.
iMedic receives no commercial funding from pharmaceutical companies. All content is independently produced and reviewed, free from conflicts of interest.