Japanese Encephalitis Vaccination - Do I need it?
Japanese Encephalitis and its Vaccination. What You Need To Know.
Japanese Encephalitis (say ‘en-kefa-lyet-is’) B is a virus transmitted by the bite from an infected mosquito (the Culex mosquito). These mosquitoes breed in rice fields and feed on pigs, duck and birds.
What is Japanese Encephalitis?
Less than 3% of the mosquitoes in infected areas carry the disease and up to 95% of humans who contract Japanese Encephalitis don’t have symptoms.
However, in those who do have symptoms, the disease is fatal in about 25% and those who survive about half will have brain damage. It can take many months to recover from the disease.
Symptoms are fever, headache convulsions, encephalitis, meningitis and vomiting.
There is no specific treatment for Japanese Encephalitis.
Where is Japanese Encephalitis?
Areas in the Far East and South-East Asia have endemic (ie low levels all the time) Japanese Encephalitis. These areas include: China, Myanmar, Thailand, Vietnam, Cambodia, Laos, Nepal, India, Philippines, Sri Lanka, Korea, Malaysia, Indonesia and Singapore and the disease is more common after the monsoon seasons.
Visitors to these areas need to discuss their risk with their health care professional. This will depend on over all health, activities while visiting the area (eg working in rural areas, jungle trekking and working with pigs) and the season and duration of travel.
How to prevent Japanese Encephalitis.
Depending on your risk factors (see above) AVOIDING MOSQUITO BITES is very important as a way of preventing disease. The Culex mosquito is most active between dusk and dawn so use of insect repellents, mosquito nets and clothing which covers the skin is essential during these hours.
A vaccine which protects against Japanese Encephalitis is available to those visitors at greater risk. 2 or 3 doses of the vaccine are needed before travel.
Side effects to the vaccination are unusual but include soreness or redness at the site of injection; very rarely anaphylaxis in response to an ingredient in the vaccine.