Japanese encephalitis is a serious disease caused by a virus. Encephalitis is an infection of the membrane around the brain and spinal cord. This infection often causes only mild symptoms, but prolonged swelling of the brain can cause permanent brain damage or death.

The Japanese encephalitis SA14-14-2 vaccine is used to help prevent this disease in people who are at least 2 months old.

This vaccine works by exposing you to a small dose of the virus, which causes the body to develop immunity to the disease. This vaccine will not treat an active infection that has already developed in the body.

This vaccine is recommended for people who live in or travel to areas where Japanese encephalitis is known to exist, or where an epidemic has recently occurred.

You should receive the vaccine and booster dose at least 1 week prior to your arrival in an area where you may be exposed to the virus.

Not everyone who travels to Asia needs to receive a Japanese encephalitis vaccine. Follow your doctor instructions or the recommendations of the Centers for Disease Control and Prevention (CDC).

This vaccine is also recommended for people who work in a research laboratory and may be exposed to Japanese encephalitis virus through needle-stick accidents or inhalation of viral droplets in the air.

Like any vaccine, the Japanese encephalitis SA14-14-2 vaccine may not provide protection from disease in every person.

Tell your doctor if you use other medicines or have other medical conditions or allergies.

This vaccine is injected into a muscle. You will receive this injection in a doctor's office or clinic setting.

The Japanese encephalitis SA14-14-2 vaccine is given in a series of 2 shots. The shots are usually 28 days apart. Your individual booster schedule may be different from these guidelines. Follow your doctor's instructions or the schedule recommended by the health department of the state you live in.

In addition to receiving the Japanese encephalitis vaccine, use protective clothing, insect repellents, and mosquito netting around your bed to further prevent mosquito bites that could infect you with the Japanese encephalitis virus.

Usual Adult Dose for Japanese Encephalitis Virus Prophylaxis:

Primary Series: Two 0.5 mL doses intramuscularly 28 days apart

Booster Dose: May give a booster dose if the primary 2 dose series was completed more than 1 year previously and ongoing exposure to Japanese encephalitis virus (JEV) is expected.

Comments: The primary immunization series should be completed at least 1 week prior to potential exposure.

Usual Pediatric Dose for Japanese Encephalitis Virus Prophylaxis:

Primary Series:
3 years of age and older: Two 0.5 mL doses intramuscularly 28 days apart
2 months to less than 3 years of age: Two 0.25 mL doses intramuscularly 28 days apart

Booster Dose:
17 years of age and older: May give a booster dose if the primary 2 dose series was completed more than 1 year previously and ongoing exposure to Japanese encephalitis virus (JEV) is expected.
2 months to under 17 years: The safety and immunogenicity of a booster dose has not been evaluated.

Comments: The primary immunization series should be completed at least 1 week prior to potential exposure.

You should not receive this vaccine if you have ever had a life-threatening allergic reaction to any vaccine containing Japanese encephalitis virus.

If you have any of these other conditions, your vaccine may need to be postponed or not given at all:

• a bleeding or blood clotting disorder; or

• a weak immune system caused by disease or by taking certain medicines or receiving cancer treatments.

You can still receive a vaccine if you have a minor cold. In the case of a more severe illness with a fever or any type of infection, wait until you get better before receiving this vaccine.

Tell your doctor if you are pregnant or breastfeeding.

Contact your doctor if you miss a booster dose or if you get behind schedule. The next dose should be given as soon as possible. There is no need to start over.

Be sure to receive all recommended doses of this vaccine. You may not be fully protected if you do not receive the full series.

An overdose of this vaccine is unlikely to occur.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

You should not receive a booster vaccine if you had a life-threatening allergic reaction after the first shot.

Keep track of any and all side effects you have after receiving this vaccine. When you receive a booster dose, you will need to tell the doctor if the previous shot caused any side effects.

Becoming infected with Japanese encephalitis is much more dangerous to your health than receiving this vaccine. However, like any medicine, this vaccine can cause side effects but the risk of serious side effects is extremely low.

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; dizziness, weakness, fast heart rate; swelling of your face, lips, tongue, or throat.

Common side effects of Japanese encephalitis virus vaccine may include:

• irritability;

• nausea, diarrhea, vomiting, loss of appetite;

• headache, tiredness;

• fever, flu symptoms;

• skin rash; or

• pain, swelling, redness, or tenderness where the shot was given.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report vaccine side effects to the US Department of Health and Human Services at 1-800-822-7967.

Before receiving this vaccine, tell the doctor about all other vaccines you have recently received.

Also tell the doctor if you have recently received drugs or treatments that can weaken the immune system, including:

• steroids (oral, nasal, inhaled, or injectable);

• chemotherapy or radiation;

• medications to treat psoriasis, rheumatoid arthritis, or other autoimmune disorders; or

• medicines to treat or prevent organ transplant rejection.

This list is not complete. Other drugs may affect Japanese encephalitis virus vaccine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.