Japanese encephalitis virus (JEV) continues to cause significant numbers of human infections and fatalities despite the availability of efficacious vaccines. It is regarded as an emerging mosquito-borne pathogen with the potential of introduction into many countries. In 2022, JEV was detected in Australia on a hitherto unprecedented scale, with local transmission by indigenous mosquitoes to amplifying swine hosts and to humans. In this study, we review this recent disease activity, propose possible routes of virus movement, ecological drivers of activity, and consider possible future transmission scenarios. Measures to enhance current surveillance systems and potential strategies for health authorities to minimize future risks are discussed.
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