Japanese Encephalitis
vaccine information
What is Japanese encephalitis?
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.
Prevention includes wearing long sleeves and long pants and observing personal protective measures effective against mosquito bites.
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.
Death occurs in about 20% to 30% of symptomatic cases. Infected children (younger than 10 years) have a greater risk of severe disease and death. Among survivors, 30% to 50% have serious neurological, cognitive, or psychiatric symptoms even years later.
Who should get the JE vaccine?
People aged 2 months and older who reside in high-risk geographical areas in Australia. Other people who work with pigs and mosquitoes are also recommended to get the JE vaccine. High risk areas are determined by state or territory governments and change over time.
What are the benefits of getting the JE vaccine?
The JE vaccine is the best way to protect against Japanese encephalitis, which is a serious and sometimes fatal disease.
Mosquitoes that transmit JEV are generally night biters but have peak biting activity at dusk and again at dawn. Regardless of vaccination status, you should be especially
vigilant in applying repellent during peak biting activity times.
Which JE vaccine can I receive?
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.
If you are receiving JEspect, you must receive two doses of JEspect at least one month apart to be protected from JE.
Boosters are not recommended for adults receiving Imojev. Boosters are recommended for people who receive JEspect and for children who receive Imojev.
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.
Who should not get the JE vaccine?
Speak with clinic staff if you are pregnant or if you or your child has an acute febrile illness or has had:
- a life-threatening reaction to a previous dose of JE vaccine, or any component of the vaccine;
- an immune system weakened by disease, a genetic disorder or medical treatment;
- a blood transfusion or received other blood products within the past 12 months.
However, if you have concerns, speak with the clinic staff.