Side Effects of the Japanese Encephalitis Vaccine
Jun 02, 2022
Source: Cainiu Health
Dr. Li Man
Introduction
Many children develop fever after receiving the Japanese encephalitis vaccine, typically a low-grade fever (<38°C), accompanied by generalized fatigue and chills. This is generally considered a normal reaction; in some cases, antipyretics may be administered for symptomatic relief. However, if the fever persists beyond 24 hours, immediate medical attention is required, and treatment should be undertaken under a physician’s guidance. Allergic reactions may also occur—rarely, some children may develop localized redness and swelling at the injection site following vaccination.
Vaccines help prevent diseases, and many newborns currently require vaccination shortly after birth. The Japanese encephalitis (JE) vaccine is one of the most commonly administered vaccines. So, what are the side effects of the JE vaccine?
Side Effects of the Japanese Encephalitis Vaccine
The most common side effect is fever. Many children develop a fever following JE vaccination—typically a low-grade fever below 38°C, accompanied by fatigue and chills. This is generally considered normal; over-the-counter antipyretics may be used for symptomatic relief. However, if the fever persists beyond 24 hours, immediate medical consultation is essential, and treatment should be guided by a healthcare professional.
Allergic reactions may also occur. Some children may experience localized redness, swelling, or pain at the injection site, or develop skin rashes. These symptoms usually resolve spontaneously as body temperature returns to normal. However, with repeated vaccinations, more severe allergic manifestations—including angioedema and even anaphylactic shock—may occur. Such adverse reactions following repeated dosing are most frequently observed in children aged seven years and older. Additionally, the live attenuated JE vaccine may cause dizziness, headache, and other systemic symptoms. Localized swelling and redness can be alleviated with warm compresses; however, if severe symptoms such as convulsions or other serious reactions occur, parents should promptly take their child to a reputable hospital for evaluation and treatment.
The Japanese encephalitis vaccine is an effective tool for preventing infection with the Japanese encephalitis virus. It is routinely recommended for infants after birth. We hope this information is helpful to you.
