In a still-active travel advisory that was put out by the CDC on 14 December 2022, the CDC discusses the Japanese encephalitis outbreak of the current year (2022) and cautions about the possibility of another recurrence.
According to the CDC, the presence of Japanese encephalitis has been detected in pigs in Australia. Unfortunately, the virus is spread by mosquitoes which can easily start spreading it back to humans. Thus it seems very likely we would see another outbreak.
The 2022 outbreak of Japanese encephalitis and the infected pigs are located in the Southeast part of Australia near Adelaide and Melbourne. The Japanese encephalitis-carrying mosquitoes are confined to the Murray River area. Murray River is Australia's longest river.
CDC recommendations: Get the Japanese encephalitis vaccine if you intend to spend more than one month in the region near the Murray River. Seek medical help immediately if you experience possible symptoms of the disease after being in the affected area. These symptoms include can include fever, headache, vomiting, disorientation, coma, or seizures.