Yellow fever vaccine: past, present and future

Background: Yellow fever is a re-emerging infectious disease, as vector control and routine immunisation have dwindled in endemic areas in the last few decades. There is a constant threat of outbreaks in the large susceptible non-immune population of the megacities in tropical countries with an ongoing virus life cycle in the rainforests. For this population and for travellers to endemic areas, vaccination is the only effective protective measure against the disease and the spread of the virus. Objective/methods: We discuss the history of yellow fever vaccine development, and focus on practical aspects of vaccine safety, contra indications for vaccination, and future vaccine developments. Results/conclusions: Vaccination with the live attenuated yellow fever-17D vaccine (YF-17D) induces low-grade viraemia in half of the vaccinees and elicits protective neutralising antibody levels in 99%. Reports of serious adverse events in the elderly and immunocompromised, and the inability to produce large quantities of yellow fever vaccine at short notice in combination with limited vaccine stockpiles highlight the need for further study of this highly effective and safe vaccine.