Japanese encephalitis is caused by the Japanese encephalitis virus (JEV). JEV is the main cause of viral encephalitis in Asia,1 and is endemic in many countries on that continent and islands of the Pacific region. Although only a small percentage of cases are symptomatic, 20–30% are fatal and 30–50% develop significant neurological sequelae.2 Australia has escaped relatively unscathed, with only a few cases detected in the late 1990s, mostly from international travellers, with local transmission limited to the Torres Strait and Cape York.2,3 The last detection of JEV in Cape York was from feral pigs and an isolate of mosquitoes in 2005. Sentinel animal surveillance in Australia was phased out in 2011 due to costs and labour‐intensive maintenance, potential occupational health and safety issues, and concerns about the potential public health risk of using amplifying hosts (pigs), which may contribute to transmission when they become viremic.3 Sentinel animal use was replaced by a general mosquito trap‐based surveillance system.3 The Box provides a timeline of JEV milestones in Australia from the 1990s to 2023, with details on animal and human cases, and corresponding changes in surveillance.
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We acknowledge the HEAL (Healthy Environments And Lives) National Research Network, which receives funding from the National Health and Medical Research Council (NHMRC) Special Initiative in Human Health and Environmental Change Initiative (Grant No. 2008937). Caroline Dowsett is funded by a Queensland University of Technology Post‐graduate Research Award (QUTPRA). We also acknowledge the National Foundation for Australia‐China Relations (Grant No. 220011), the Australian Department of Foreign Affairs and Trade.
No relevant disclosures.