Developing a vaccine against dengue remains a challenge. There are four closely related viruses that can cause disease, and the goal for a vaccine is to protect against all four. There is limited understanding of how severe disease occurs and how the virus interacts with the immune system. There is also no correlate of protection, which is a measurable sign (such as antibodies) that a person is immune, and no laboratory animal models available that reliably predict that a vaccine will protect a person against dengue. Despite efforts to control dengue, based primarily on vector control and case management, the burden and costs of the disease continue to grow. It is currently estimated that more than 96 million symptomatic dengue cases occur each year. Prevention by vaccination is feasible, and vaccines are needed.
Five vaccine candidates are in clinical stages of development. Many other dengue vaccines are under development but are still being tested in pre-clinical trials (not in humans) (click on table below to enlarge).