As with any live attenuated vaccine, yellow fever vaccine must not be given to people who are clinically immunosuppressed. This includes a history of thymus dysfunction (including myasthenia gravis and thymoma).
Recently 2 reports of fatal adverse reactions to yellow fever vaccine have been notified. In 1 case, vaccine was given to a person with a history of thymectomy following a thymoma. In another case, vaccine was given to a 67-year-old with no other known risk factors. Both patients died shortly after vaccination due to suspected yellow fever vaccine-associated viscerotropic disease (YEL-AVD). YEL-AVD is a recognised adverse reaction that resembles severe yellow fever infection. The global reporting rate is around 1 case in every 1 million people vaccinated, with thymus disease, immunosuppression, and an aged ≥60 years increasing the risk. Another serious risk of vaccination is vaccine-associated neurotropic disease (YEL-AND), occuring at a similar rate and with same risk factors.
For full prescribing information and warnings, precautions, and risks, refer to Summary of Product Characteristics.
Due to a higher risk of severe and potentially fatal adverse reactions, in people aged ≥60 years, vaccine should only be given when it is considered that there is a significant and unavoidable risk of acquiring yellow fever infection.
Professionals who administer yellow fever vaccine must be familiar with any contraindications and special precautions before proceeding with immunisation. Any healthcare professional prescribing or administering vaccine must ensure they are fully familiar with up-to-date Summary of Product Characteristics . More information and guidance on yellow fever vaccine can also be found in Green Book and National Travel Health Network and Centre (NaTHNaC) website.
If there is any doubt as to whether a person who is due to receive yellow fever vaccine may be immunosuppressed, immunisation should be deferred until specialist advice has been sought. Protocols and checklists should be strengthened to avoid inappropriate administration that can lead to severe and possibly fatal adverse effects; those administering vaccine should also be familiar with YF Vaccine Centre code of practice. NaTHNaC recommends that health professionals use a travel risk assessment form to guide travel health consultation and seek specialist advice when a significant medical history is identified. More information on yellow fever, and YF Vaccine Centre code of practice can be found on NaTHNaC website.
Healthcare professionals are advised to report suspected adverse drug reactions vaccines and other medicines via the Yellow Card Scheme.