JAPANESE ENCEPHALITIS (JE) is a mosquito-borne disease. The virus is transmitted when infected Culex mosquitoes bite us.
These mosquitoes breed in places where there is abundant water, such as rice paddies. They feed mainly on the blood of domestic animals, like pigs. Therefore, JE is mostly found in the rural and agricultural areas of Asia and the Western Pacific Region, but is rare in Hong Kong. The fact that the virus is not directly transmitted from person to person should also ease our minds.
Most JE infections are asymptomatic. The incubation period varies from five to 15 days. Patients usually have a headache and fever and feel nauseous. In severe cases, they may become disoriented and lapse into a coma.
There is no specific treatment for this disease.
Travellers can protect themselves by taking simple precautionary measures. Avoid going outdoors at dusk or dawn, when mosquitoes are most active. If you have to be in an open rural area, you are advised to wear a long-sleeved top and trousers. Apply insect repellents to the exposed parts of your body.
Vaccination is generally recommended for people who will be spending 30 days or more in a rural area, where the disease may be endemic.
