Overview
Hepatitis A is transmitted through faeces and can contaminate unwashed foods.
Hepatitis A vaccine is recommended for some people whose occupation puts them at risk of exposure to faeces (poo/tūtae) or involves food preparation, and for people travelling overseas.
Avaxim is available for purchase as an alternative vaccine to purchasing a Havrix vaccine dose.
Responses to vaccine
- Mild pain, redness and swelling around injection site
- Fatigue
- Muscle aches and pains
- Headache
- Fever
- Nausea, vomiting, loss of appetite
- Irritability
- Urticaria (hives)
Other formulations and brands
Other brands:
- Havrix Junior, approved for use for children from 1 year of age and adolescents to 16 years of age.
- Havrix 1440, approved for use for adolescents from 16 years of age and adults.
Combination vaccines that include hepatitis A:
- Twinrix (combination hepatitis A and B vaccine)
- Hepatyrix and Vivaxim (combination hepatitis A and typhoid vaccines)
Schedule and administration
Axaxim is not funded in New Zealand but is available for purchase as an alternative to Havrix.
Avaxim is recommended but not funded for certain occupations at risk of exposure to faeces or involved in food preparation:
- Early childhood employees
- Carers of people with developmental disabilities
- Healthcare staff, including cleaners
- Sex industry workers
- People exposed to sewerage
Additionally, the vaccine is recommended for:
- Correctional facility inmates
- Men who have sex with men
- Injecting drug users
- Recipients of blood products, such as factor VIII
- Persons with chronic liver disease or who are at risk of developing chronic liver disease, e.g. people who are hepatitis B or hepatitis C positive, people who misuse alcohol
Storage and preparation
Store as per cold chain between 2°C to 8°C. Shake the prefilled syringe before injection to obtain a homogenous suspension.
Administration
Avaxim is given as a single dose of vaccine administered by intramuscular injection for children and adults. A second vaccination 6-12 months later acts as a booster vaccination to extend the duration of protection.
It can be administered concurrently with other vaccines, including all the National Immunisation Schedule vaccines. Separate syringes and different injection sites should be used.
The vaccine can be administered at the same visit, using a different injection site, as immunoglobulin (Ig) for persons requiring hepatitis A vaccination for post-exposure prophylaxis.
Vaccine Safety
Avaxim should not be given to:
- Anyone with severe allergy (anaphylaxis) to a previous dose of this vaccine or other hepatitis A containing vaccine, or a component of the vaccine
- Administration of Avaxim should be postponed in individuals suffering from a fever over 38°C. The presence of a minor infection is not a reason to delay immunisation
The vaccine can be administered to pregnant and breastfeeding women at high risk of the disease e.g. travelling to a hepatitis A endemic area or a close contact of a hepatitis A case.
Specialist advice should be sought for the following groups:
- Those with bleeding disorders, such as haemophilia. The vaccine should be administered in accordance with the haematologist’s instructions. It may, in this situation only, be given subcutaneously
Vaccine Effectiveness
A serology result of ≥20 mIU/mL is considered to demonstrate immunity to hepatitis A.
Immunisation against hepatitis A protects 9-10 out of 10 people against the disease. Clinical trials indicated that after the second dose, protection lasts for at least 17 years, possibly up to 30-40 years. A recent review concluded that protective antibody levels to hepatitis A could be present for at least 25 year in adults and at least 14-20 years in children following a two dose course of vaccine.
In clinical trials, 15 days after vaccination 88% of healthy vaccine recipients aged 16–50 years and 93% aged 1–16 years were protected against hepatitis A. One month after vaccination 99% of healthy recipients aged 1—50 years were protected against the disease.
References
- Ezeanolue E, Harriman K, Hunter P, Kroger A, Pellegrini C. Centers for Disease Control and Prevention. General Recommendations on Immunization Recommendations of the Advisory Committee on Immunization Practices (ACIP);[updated 2020 July 27; cited 2020 September 30]. Available from: https://www.cdc.gov/vaccines/hcp/acip-recs/general-recs/downloads/general-recs.pdf
- Health New Zealand | Te Whatu Ora, Immunisation handbook [Internet]. Available from: https://www.tewhatuora.govt.nz/for-health-professionals/clinical-guidance/immunisation-handbook