The responsibility of thwarting and managing Japanese encephalitis cannot be understated—Outbreaks or resurgences may manifest, catching us off guard

Japanese encephalitis virus (JEV) is a flavivirus with a single-stranded positive RNA genome mainly distributed in Asia and the Western Pacific.By 2022, it had spread to the south of Cairns, Australia.Japanese encephalitis (JE) is an acute zoonotic infectious disease mainly transmitted through mosquito bites, particularly in rural areas and during seasonal peak disease periods.It is mainly characterized by central nervous system diseases and is associated with acute onset, severe illness, high disability rate, and a heavy disease burden.Some severe patients have left serious neurological sequelae [1].There is no specific treatment for JE at present, and mosquito control has failed to eliminate the disease.Fortunately, JE is a vaccinepreventable disease, and vaccination remains a critical means of preventing and controlling JE [2].Since the implementation of the planned immunization of JE vaccine in 2008, the incidence rate of JE in children has significantly reduced in China, where the disease has been prevalent for a long time.However, despite the effective vaccines, JE remains a grave health threat in numerous underdeveloped countries and regions due to the lack of good medical equipment and human resources, as well as the relatively weak public awareness of disease prevention.For example, among all etiological factors of flavivirus infections, JE causes the highest hospitalization rate and the most serious disease burden among Chinese children [3].Additionally, adult cases are also exhibiting a gradual increase [4], underscoring the ongoing relevance of JE as a potential public health concern, which poses a substantial threat to the well-being of the population.In recent years, the prevention and control of the JE epidemic has encountered new situations and challenges.Firstly, the spread of JEV has extended to nontraditional epidemic areas [5].With a high variability, strong adaptability, diverse storage, and transmission hosts, the virus can spread and circulate among animals for long period, making it challenging to eliminate.Climate change, as well as frequent human movement, further increases the transmission risk and extends the monitoring area and objects.Secondly, JEV genotypes coexist and switch, and the risk of emergence and reemergence of JEV genotype V increases.Based on envelope protein nucleotide sequence differences, JEV is categorized into 5 genotypes (GI to GV), each with its geographical distribution characteristics.Certain genotypes of JEV are capable of generating elevated viremia levels with prolonged durations in ducklings and chicks, coupled with diminished interferon (IFNAU : Pleasenotethat}IFN}hasbeenaddedafter}interferon}asitsabbreviation) production [6,7], making the virus better suited for bird hosts.