Questions & Answers
Japanese encephalitis - The Vaccine
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  1. Who should not receive the JE vaccines?

    People who had a severe allergic reaction to a previous dose of IXIARO® or other JE vaccine, or are allergic to any component of IXIARO®, including protamine sulfate, should not be vaccinated.  IXIARO® contains protamine sulfate, known to cause hypersensitivity reactions in some individuals.

    Safety and effectiveness of IXIARO® has not yet been established in pregnant women or nursing mothers.  Pregnant women should generally not receive JE vaccine.  Check with your doctor since it could be recommended under certain circumstances.

    If you will be traveling for fewer than 30 days, especially if you will be staying in major urban areas, tell your doctor.  You may be at a lower risk and not need the vaccine.

  2. What should I tell my health care professional before I am vaccinated with IXIARO®?

    It is very important to tell your health care provider if you:

    • have had an allergic reaction to a previous dose of IXIARO or any other JE vaccine;
    • have a bleeding disorder or a reduction in blood platelets, which increases risk of bleeding or bruising (thrombocytopenia) and cannot receive injections in the arm;
    • have a weakened immune system, for example, due to a genetic defect or HIV infection;
    • are or may be pregnant, or are breast feeding - IXIARO has not been studied in pregnant women or nursing mothers;
    • currently have any illness with a fever of more than 100°F (37.8°C);
    • take any medicines, even those you can buy over the counter.