What is Japanese Encephalitis?
Japanese Encephalitis (JE) is a virus-disease that is transmitted by mosquitos. It lives in humans, pigs and birds. When a mosquito bites an infected animal, it can then transmit the disease by biting someone else. An infected person is unable to infect another person through mosquito bites.
Culex spp. mosquito responsible for transmitting JE
This virus then infects the brain causing inflammation of the brain. Approximately 1 in 4 cases of JE is fatal.
Fortunately, less than 1% whom are infected with the JE virus actually develop the illness.
What are the symptoms of JE?
Once infected by the JE virus, it takes about 5-15 days to develop symptoms.
Initially symptoms include
- Fever
- Headache
- Vomiting
Later symptoms include
- Change in mental status. This means that the person might be acting differently from his/her usual self.
- Muscle weakness and problems with moving properly
- Seizures (more common in children)
Prevention and treatment
Prevention
1) Avoid mosquito bites.
- Wear long sleeves clothing where possible to prevent bites
- Use mosquito repellents
- Avoid exposure to mosquitos during peak biting hours (from dusk to dawn).
2) Get vaccinated if recommended
- People living in endemic areas or areas of outbreak.
- Travellers going to areas of outbreak regardless of duration
- Travelers going to JE virus endemic areas and are going to spend >1 month there should get vaccinated.
- Travelers going to JE virus endemic areas and are going to spend <1 month there but is going to areas that are not urban should get vaccinated.
- Travelers going to JE virus endemic areas and are going to spend <1 month and staying in areas that are urban does NOT need to get vaccinated.
Treatment
So far, there is no effective treatment for JE. Patients will be hospitalized and given supportive care and close observation. Medications for fever, fluids and also pain relievers may be given, but there is no medications that is useful to treat the viral infection itself.
Outcome
About 20% to 30% of patient dies.
Of the survivors, 30% to 50% continue to have some neurologic, psychiatric or memory problems.
References:
Cdc.gov. (2018). Japanese Encephalitis | CDC. [online] Available at: https://www.cdc.gov/japaneseencephalitis/index.html [Accessed 1 Jul. 2018].
World Health Organization. (2018). Japanese encephalitis. [online] Available at: http://www.who.int/news-room/fact-sheets/detail/japanese-encephalitis [Accessed 1 Jul. 2018].
Cover image credit: AAFP
