Japanese encephalitis

Japanese encephalitis is a mosquito borne virus from the family Flaviviridae. Domestic pigs and wild birds are reservoirs of the virus; transmission to humans may cause severe symptoms. One of the most important Vectors of this disease is the mosquito Culex tritaeniorhynchus.

The disease is caused by a flavirus that affects the membranes around the brain.

Severe rigours mark the onset of this disease in Humans. Fever, Headache and malaise are other non-specific symptoms of this disease, which may last for a period between 1 to 6 days.

Signs, which develop during the acute encephalitic stage, include neck rigidity, cachexia, hemi paresis, convulsions and a raised body temperature between 38 and 41 degrees Celsius. Mental retardation developed from this disease usually leads to coma. Mortality of this disease varies but is generally much higher in children.

Japanese encephalitis is a leading cause of viral encephalitis in Asia with 30-50 million of clinical cases reported annually. Intensification and expansion of irrigated rice production systems in South-East Asia over the past 20 years have had an important burden caused by this disease. The flooding of the fields at the start of each cropping cycle leads to a big growth of the mosquito population.

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Sources:
http://www.who.int/water_sanitation_health/diseases/encephalitis/en/
http://www.answers.com/japanese%20encephalitis
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