Abstract Purpose of Review Recent changes in Japanese encephalitis (JE) distribution, including its emergence in mainland Australia, call for a review of the epidemiology, diagnosis, treatment and prevention of this important disease. Recent Findings Climate change, urbanisation and changes in vector ecology have driven changes in JE epidemiology including expansion to new areas. Residents of and travellers to endemic areas face potential exposure risks. Surveillance gaps and diagnostic challenges lead to under-appreciation of the true disease burden. Treatment is supportive, but modern vaccines are safe and efficacious. Summary The recent emergence of JE in south-eastern Australia highlights its changing epidemiology and the threat this disease poses to other areas with largely naive human populations and with competent mosquito vectors and vertebrate hosts. Awareness of disease features and diagnostic approaches is critical to case detection in travellers and endemic populations, and preventive measures including vaccination should be advised for those with exposure risk.