Japanese encephalitis vaccine

Japanese Encephalitis Vaccine is a vaccine used to protect against Japanese encephalitis (JE), a viral infection spread by mosquitoes in Asia and parts of the western Pacific. The disease primarily affects the brain and can lead to serious complications or death. The vaccine is recommended for people living in or traveling to areas where Japanese encephalitis is common, and for those at increased risk of exposure to the virus.

Types of Vaccines

There are several types of Japanese encephalitis vaccines available, including inactivated vaccines and live attenuated vaccines. The most commonly used vaccines are:

• Inactivated Vero cell vaccine (e.g., IXIARO, JESPECT), which is grown in cell cultures and then killed to prevent it from causing disease.
• Live attenuated vaccine (e.g., SA 14-14-2), which uses a weakened form of the virus that cannot cause disease in healthy individuals.

Efficacy and Recommendations

The World Health Organization (WHO) recommends the Japanese encephalitis vaccine for individuals living in or traveling to endemic areas, especially where the disease is a known public health issue. The vaccine has shown high efficacy in preventing Japanese encephalitis, with protection rates exceeding 90% in clinical trials.

Vaccination Schedule

The vaccination schedule may vary depending on the specific vaccine used. Generally, the inactivated vaccine is administered in two doses, 28 days apart. A booster dose may be recommended for ongoing protection. The live attenuated vaccine is usually given as a single dose, with a booster dose recommended every 1 to 2 years for those at continued risk.

Side Effects

Side effects of the Japanese encephalitis vaccine are generally mild and may include pain at the injection site, headache, muscle pain, and fever. Serious side effects are rare but can include allergic reactions.

Travel Considerations

Travelers to endemic areas should consider vaccination at least 1 month before travel to allow sufficient time for immunity to develop. Vaccination is particularly important for those planning to spend extended periods in rural or agricultural areas where the virus is more prevalent.

Prevention and Control

In addition to vaccination, other preventive measures against Japanese encephalitis include using insect repellent, wearing long sleeves and pants, and staying in accommodations with effective mosquito protection.

See Also

• Vaccination
• Viral encephalitis
• Mosquito-borne disease
• Travel medicine