Yellow fever vaccine

Indications

Prevention of yellow fever in children from 9 months of age and adults living in, travelling to, or travelling from endemic areas, and in mass immunisation campaigns during outbreaks.

Composition, forms, route of administration

• Live-attenuated virus vaccine, prepared by culturing the virus in embryonated chicken eggs.
• Powder for injection in monodose and multidose vials, to be dissolved with the entire vial of diluent supplied by the manufacturer.
• For IM injection into the anterolateral part of the thigh in children under 2 years and into the deltoid muscle in children 2 years and over and adults.

Dose and vaccination schedule

• Child and adult: 0.5 ml single dose.
• In routine immunisation, the vaccine is usually administered between 9 and 12 months of age, along with the measles vaccine.
• A standard 0.5 ml single dose by IM injection is sufficient to confer life-long immunity. A booster dose is no longer recommended.
• Only in the event of limited vaccine supply during yellow fever outbreaks and according to national recommendations, vaccination may be administered by SC or IM injection in children over 2 years and adults with a fractional dose of one half or one fifth of the standard dose, minimum 0.1 ml, using vials containing a maximum of 10 standard doses.
• Children under 2 years, pregnant women, and HIV positive individuals are administered a standard 0.5 ml dose by IM injection.

Contra-indications, adverse effects, precautions

• Vaccination is contra-indicated in children less than 6 months. In children between 6 and 9 months, vaccination is only recommended in epidemics, when the risk of virus transmission may be very high.
• Do not administer to patients with history of allergy to egg, to immunocompromised patients, or to patients with symptomatic HIV infection or under immunosuppressive treatment.
• Vaccination should be postponed in the event of severe acute febrile illness; minor infections are not contra-indications.
• May cause mild reactions at the injection site, mild fever, headache, myalgia, and rarely hypersensitivity reactions, neurological disorders, or multiple organ failure, especially in adults over 60 years.
• If administered simultaneously with other vaccines, use different syringes and injection sites.
• Pregnancy: not recommended, but given the severity of yellow fever the vaccine may be administered when the risk of contamination is very high.
• Breast-feeding: no contra-indication.