The Japanese encephalitis (JE) situation in Australia has been declared a Communicable Disease Incident of National Significance as of March 2022. JE is a vaccine preventable disease caused by the Japanese encephalitis virus (JEV). The Australian Technical Advisory Group on Immunisation (ATAGI) and the Communicable Diseases Network of Australia (CDNA) have developed resources outlining information on the vaccines available to prevent JE and who they are recommended for. 

The Australian Government Department of Health has also developed a 'Health alert' web page for JEV, which is updated regularly with the latest information and medical advice.

The Australian Immunisation Handbook has a chapter on Japanese encephalitis. Access the chapter here.

Japanese encephalitis learning resource for registered nurses and midwives

A learning resource has been developed to support registered nurses and midwives administering the JE vaccine. This resource provides information on JE and the vaccines available to reduce the risk of spread of the JE virus. 

Access the learning resource here

Japanese Encephalitis: Frequently asked questions

We have provided answers to some of the most frequently asked questions about Japanese Encephalitis vaccines. We update this page regularly (last updated 11 August 2023).

  • What is the difference between Japanese encephalitis and Murray Valley encephalitis (MVE)?

    The JE and Murray Valley encephalitis (MVE) viruses are closely related but different from one another. They can both be spread by the same species of mosquitoes. There are only vaccines against the JE virus. Currently, we do not have evidence that the JE vaccines protect people against the MVE virus.

    Further information about MVE is available from the government-funded service healthdirect as well as on your state and territory health department website.

  • What is Japanese encephalitis, and how is it passed on?

    Japanese encephalitis (JE) is a rare but serious infection of the brain caused by the Japanese encephalitis virus (JEV). JEV can be spread to humans by some types of mosquitoes. A mosquito can become infected by biting infected animals such as pigs or waterbirds, and can then pass on the infection by biting a human. Humans are not able to transmit JEV to another human or mosquito. Humans cannot get JEV by touching or eating meat from an infected animal.

    Most people who get JEV will show no symptoms. A small proportion (less than 10%) of people may experience fever, headache or vomiting. People with severe infection may develop encephalitis: neck stiffness, coma, seizures, disorientation and, potentially, permanent neurological complications or death. Less than 1 in 200 people who get infected with JEV will develop encephalitis.

  • Who is eligible to receive a JE vaccine?

    ATAGI recommends JE vaccination to people aged 2 months and older who reside in high-risk settings in Australia. Your state or territory will determine if you are in a high risk setting and are eligible to receive JE vaccination.

    For more information, refer to your state or territory webpage:


    Vaccines are currently being prioritised for people most at risk of JEV. Eligibility for vaccination may change in the future. Where available, ATAGI also routinely recommends JE vaccination for people travelling to endemic areas, and for residents of the Torres Strait Islands. Talk to your doctor for more information. 

  • Which JE vaccine can I receive?

    There are 2 JEV vaccines available in Australia: Imojev and JEspect (also known as Ixiaro). Both vaccines are safe and effective. Which vaccine you receive will depend on age, pregnancy status, whether or not you are immunocompromised and availability.

    Imojev is available for people who are aged 9 months and older. Pregnant women and immunocompromised people cannot receive Imojev as it is a live attenuated vaccine. Women should avoid pregnancy for 28 days after vaccination with Imojev.

    JEspect is available for people who are aged 2 months and older. It is recommended for pregnant women, immunocompromised people and children aged 2 months to less than 9 months, as they cannot receive Imojev. 

    For more information refer to the ATAGI clinical guidance on Japanese encephalitis virus vaccines

  • Are the JE vaccines safe?

    The JE vaccines are very safe. All vaccines in Australia undergo an approval process by the Therapeutic Goods Administration, involving a rigorous assessment of vaccine effectiveness and safety. The vaccines continue to be monitored for safety once they have been approved and are being administered on a population level. 

    Any side effects that you may experience after receiving JE vaccination are generally mild and will resolve within a few days. Common side effects include pain at the injection site, headache and fatigue.

  • Can pregnant women receive the JE vaccine?

    Yes, pregnant women can receive 2 doses of the JEspect vaccine. Pregnant women cannot receive the Imojev vaccine as it is a live attenuated vaccine and these vaccines are generally contraindicated in pregnant women. Women should avoid pregnancy for 28 days after vaccination with Imojev.

    Women who are breastfeeding are recommended to receive JEspect, however Imojev can be given.

    There have been no safety concerns in pregnancy related to the JEspect vaccine. See the ATAGI clinical guidance on Japanese encephalitis virus vaccines.

  • Can the JEspect vaccine and the Ixiaro vaccine be given interchangeably for dose 1 and dose 2?

    Yes, JEspect and Ixiaro can be given interchangeably. The vaccine registered as JEspect in Australia is registered as Ixiaro in some countries overseas. Ixiaro is an equivalent brand product to the JEspect vaccine. Recommendations by ATAGI on the use of Ixiaro are equivalent to those for JEspect.

    The JEspect and Ixiaro vaccines are not interchangeable with the Imojev vaccine. If you have received dose 1 of JEspect or Ixiaro, you should receive the JEspect or Ixiaro vaccine as the 2nd dose. The Imojev vaccine only requires 1 dose. 

    If you have been previously vaccinated with a JE vaccine not used in Australia, you can receive either Imojev or JEspect if you have an ongoing risk of JEV exposure.

  • Are booster doses required and who should receive a booster dose?

    Yes, some people may require a booster dose of either Imojev or JEspect. If you have been recommended to receive JE vaccination and it has been more than 1 year since you finished a primary JE vaccine course, a booster dose is recommended if you’re still at risk. 

    An exception to this is if you have evidence to show that you received a dose of Imojev when you were 18 years or older. In this case, you will not require a booster dose. 

    If possible, the same vaccine used in the primary course should be used as the booster dose, as there is no evidence on the interchangeability of Imojev and JEspect. However, using a different vaccine brand for the booster dose should produce a good immune response and there are no theoretical safety concerns.

  • I have already received a JE vaccine. Do I need another one?

    If you have been recommended to receive JE vaccination and it has been more than 1 year since you finished a primary JE vaccine course, a booster dose is recommended if you’re still at risk. The exception is: if you have evidence to show that you received a dose of Imojev when you were 18 years or older, you will not require a booster dose. 

    If you are recommended to receive a booster dose, the same vaccine used in the primary course should be used as the booster dose as there is no evidence on the interchangeability of Imojev and JEspect. However, using a different vaccine brand for the booster dose should produce a good immune response and there are no theoretical safety concerns.

  • Is serology (blood) testing required before giving JE vaccinations?

    No, you do not need to have a serology (blood) test before receiving JE vaccination. If you have evidence of antibodies to JEV you can still receive the vaccination. If you are in high-risk settings, you can access vaccination in line with state and territory recommendations.

  • How is the JE vaccine administered?

    Imojev is administered via subcutaneous injection. JEspect is administered via intramuscular injection. The deltoid region is the recommended site for intramuscular and subcutaneous vaccination in adults and children ≥12 months of age.

    Further information regarding administration JE vaccines is available in the Australian Immunisation Handbook.

  • Can JE vaccines be co-administered with other vaccines?

    Yes, Imojev and JEspect can be co-administered with other vaccines if required. If co-administering a JE vaccine with another vaccine, it is recommended to administer the vaccines in different limbs.

    Imojev is a live attenuated vaccine. Imojev should be administered 4 weeks apart from another live vaccine if they are not administered at the same time. For more information refer to the Australian Immunisation Handbook.

  • Who can administer the vaccine?

    Vaccination providers for JE vaccines vary by State and Territory. They may include general practitioners (GPs), pharmacists and/or nurse immunisers depending on your local State or Territory legislation. 

    For more information refer to your state or territory webpage:

  • How do I report JE vaccines to the AIR?

    All JEV vaccines administered should be reported to the Australian Immunisation Register (AIR). All individuals, including those without a Medicare card, should have their vaccines recorded on the AIR. 

    Providers can submit encounters via their practice management software or directly onto the AIR site. Information for providers about how to record and update immunisation details is available on the Services Australia website.
     

  • Where can I get further information about JE vaccines?

    Further information about JE vaccines can be found:


    The JE vaccines, Imojev and JEspect, are not new vaccines. They are widely used and have been available in Australia for many years. For more information on the safety of JE vaccines, refer to the ATAGI clinical guidance on Japanese encephalitis virus vaccines.