Yellow Fever Vaccine (Systemic)

Brand name(s): YF-Vax

Before Using This Medicine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For yellow fever vaccine, the following should be considered:

Allergies-Tell your doctor if you have ever had any unusual or allergic reaction to yellow fever vaccine. Also tell your doctor if you are allergic to any other substances, such as foods (especially eggs and chicken), preservatives, or dyes. The yellow fever vaccine available in the U.S. and Canada is grown in chick embryo cell culture so it may contain egg or chicken protein.

If you are allergic to eggs or chicken, your doctor may have to do a skin test before giving you the vaccine. However, if you need the vaccine because of international travel requirements, not because you are traveling to a country where there is a high risk of getting yellow fever, you may ask your doctor for a waiver letter stating the reason why you cannot be vaccinated.

Pregnancy-Yellow fever vaccine may cause birth defects. Therefore, it is not recommended for use in pregnant women, especially in the first 3 months of pregnancy, unless they are at high risk of getting yellow fever. Pregnant women who have not already been immunized are generally advised to postpone their travel and vaccination until after giving birth.

If travel to high-risk areas cannot be postponed, pregnant women should be vaccinated. The chance of getting serious problems from infection with yellow fever in those areas is much greater than the chance of getting a serious side effect from the vaccine for both the mother and the fetus.

However, a pregnant woman who needs the vaccine because of international travel requirements, not because she is traveling to a country where there is a high risk of getting yellow fever, may ask the doctor for a waiver letter (official-looking on letterhead stationery) stating why she cannot be vaccinated.

Breast-feeding-Yellow fever vaccine has not been shown to cause problems in nursing babies.

Children-Yellow fever vaccine is recommended for children 9 months of age or older if they are traveling to, or living in, areas where there is yellow fever infection, or if they are traveling to areas that require yellow fever immunization (certificate of vaccination). In special cases, such as high-risk exposure, yellow fever vaccine may be given to children 4 to 9 months of age. However, the vaccine is not recommended for infants younger than 4 months of age, because of an increased chance of serious side effects.

Other medicines-Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Before you receive yellow fever vaccine, it is especially important that your doctor know if you have received any of the following:

• Treatment with x-rays or medicines that may lower the body's protection against infection such as those used for organ transplants (e.g., cyclosporine), cancer medicines, or corticosteroids-May decrease the useful effect of yellow fever vaccine

Other medical problems-The presence of other medical problems may affect the use of yellow fever vaccine. Make sure you tell your doctor if you have any other medical problems, especially:

• Immune deficiency condition (or family history of)-The condition may decrease the useful effect of the vaccine or may increase the risk and severity of side effects

• Serious illness with fever-The symptoms of the illness may be confused with the possible side effects of the vaccine