Yellow Fever Vaccination Vaccination schedule The vaccination comprises a single subcutaneous injection administered from the age of 9 months onwards. The vaccine confers at least 10 years of immunity in nearly 100% of recipients. Yellow fever vaccination certificate is now the only international vaccine certificate required for entry into countries. Travellers should remember that the international certificate is valid only 10 days after the primary immunisation, therefore adequate time should be allowed for vaccination before departure. Booster dose is required every 10 years. Recommendations Yellow fever occurs only in parts of Africa, Central and South America. Travellers visiting the endemic zone should consider vaccination and carry the vaccinecertificate. Since the actual area of the endemic zone varies from time to time, travellers should take note of this and consult their doctors for opinions. Adverse reactions 5-10% of recipients will experience mild headache, low-grade fever, fatigue and myalgia between fourth to seventh days after immunisation. Immediate allergic reaction is very rare. However, cases of anaphylaxis have been reported. Contraindications The contraindications for yellow fever vaccination include: Having a febrile illness. Person known to have hypersensitivity reactions to neomycin, polymyxin and egg. Pregnant women. Infants under six months old. On immunosuppressive treatment or having radiotherapy. Suffering from immunosuppressive diseases such as lymphoma, thymoma, leukaemia, Hodgkin' s disease and hypogammaglobulinaemia. If other live vaccines are required, 3 weeks of interval time are needed between injections. Safety is uncertain in both symptomatic or asymptomatic HIV positive individuals.