The World Health Organization (WHO) estimates that dengue viruses are responsible for more than 50 million cases of dengue fever and approximately one half million cases annually of the more severe disease, dengue hemorrhagic fever/shock syndrome (DHF/DSS). Infection with dengue viruses is the leading cause of hospitalization and death in children in at least eight tropical Asian countries.
There are four serotypes of dengue virus (DEN1, DEN2, DEN3, and DEN4), each capable of causing dengue illness ranging from a mild, self-limited febrile illness to life-threatening disease.
Dengue viruses are endemic in most tropical and subtropical regions of the world with more than 2 billion persons at risk for acquiring dengue. The WHO has made development of a dengue vaccine a top priority.
The goal of immunization is to induce a long-lived neutralizing antibody response against all four dengue serotypes. This can be best achieved using a tetravalent live attenuated virus vaccine delivered in one or more doses. Development of a live-attenuated vaccine is a reasonable goal since it has already been achieved for the related yellow fever virus.
Two kinds of live dengue virus vaccines are under development:
- Vaccines based on dengue viruses attenuated through serial passage in tissue culture, such as PGMK cell-derived attenuated dengue viruses
- Vaccine derived by site-directed mutagenesis of infectious DNAs. Two strategies are being used for molecular attenuation:
- Site-directed mutagenesis of virulent viruses
- Chimerization with genes from attenuated viruses.
Division of Vector-Borne Infectious Diseases
Epidemic and Pandemic Alert and Response
National Institute of Allergy and Infectious Diseases
Here is a link to information about participating in Dengue virus vaccine studies at the CIR.