For most people (around 99%), there will be no symptoms of infection. However, in a small number of cases, symptoms of Japanese encephalitis may begin 5-15 days after infection from a mosquito bite.

For most people (around 99%), there will be no symptoms of infection. However, in a small number of cases, symptoms of Japanese encephalitis may begin 5-15 days after infection from a mosquito bite.
The initial symptoms may be severe shivering and chills, fever, headache, nausea and a stiff neck. Neurological (nervous system) symptoms may include disorientation, unconsciousness, tremors, seizures, convulsions, paralysis, coma, and death. Recovery can take a long period of time, and carries a high likelihood of on-going neurological symptoms, including deafness and partial paralysis.
Less than 1% of people infected with the Japanese encephalitis virus develop clinical illness.
2. NSW Government Department of Health. Japanese encephalitis fact sheet. Available at: https://www.health.nsw.gov.au/Infectious/factsheets/Pages/japanese_encephalitis.aspx (accessed 16 November 2021).
6. Centers for Disease Control and Prevention. Japanese encephalitis – symptoms & treatment. Available at: https://www.cdc.gov/japaneseencephalitis/symptoms/index.html (accessed 16 November 2021).
MAT-AU-2102454 Date of preparation December 2021
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