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Japanese Encephalitis

What is Japanese Encephalitis? 

Culex mosquitoes spread Japanese Encephalitis. The disease is spread to humans via the bite of an infected mosquito which breeds in rice fields and feeds on pigs, birds and ducks. Only 1-3% of mosquitoes in endemic areas carry the disease. In those humans who are infected 95.5% remain asymptomatic. While infection rates are small, of those who develop symptoms the disease is fatal in around 25% usually occurring within the first 10 days. Of those who survive up to 50% are left with brain damage. Symptoms include fever, headache and vomiting. Recovery can take many months in those who survive.

Who is at risk of Japanese Encephalitis? 

Any traveller to areas where Japanese Encephalitis is endemic (that is: the infection is present in low levels) is at risk. This includes areas of the Far East and Southeast Asia. 

How can I prevent Japanese Encephalitis? 

For those at high risk a good vaccine is available and suitability should be discussed with a health professional. For low risk areas and short trips, bite prevention is the best method of prevention. Repellents should be applied from dusk to dawn.