Japanese encephalitis (JE) is a rare but serious disease of the brain that is caused by the Japanese encephalitis virus (JEV).
The Japanese encephalitis virus is spread by infected mosquitos. Mosquitoes transmit the disease to humans and other animals, such as waterbirds, pigs and horses.
Waterbirds and pigs are important in the JEV transmission cycle as they can pass the virus back to biting mosquitoes.
JEV is typically found throughout Asia and the Pacific region, with historically a small number of notifications in far north Queensland, the Torres Strait and the Tiwi Islands in the Northern Territory.
It is important to note that Japanese encephalitis cannot be directly transmitted (by direct contact) from person to person, animal to person, or by eating meat from an infected animal.
In most cases, people infected with the Japanese encephalitis virus don’t develop symptoms.
Severe symptoms of Japanese encephalitis however can include:
In rare cases (less than 1 percent), encephalitis (swelling of the brain) may occur, and can result in long-term damage to the nervous system, or death.
Children under 5 years old or elderly people are at a higher risk of developing encephalitis.
If someone is infected with the Japanese encephalitis virus while pregnant, it can increase the risk of miscarriage and other complications.
There is a vaccination which provides protection against Japanese encephalitis.
People who wish to be vaccinated against JEV for travel purposes should visit their GP or travel medicine clinic for a private prescription.
As vaccine effectiveness takes a few weeks to develop, it’s best to prepare in advance and consult with a doctor for the best time frame to receive the dosage.
The WA Department of Health is currently offering free JE vaccine to eligible persons in specific areas of the Kimberley and Pilbara. These areas are considered to be at highest risk of JEV transmission in WA, either because JEV has been detected nearby or because there are habitats nearby that could support JEV spread (wetlands, large numbers of waterbirds or feral pigs and JEV carrying mosquitoes). For everyone else, there is a cost.
