Dengue vaccine development and dengue viral neutralization and enhancement assays

Dengue fever is a major tropical infectious disease that affects 50–100 million people each year. Its complications, namely dengue haemorrhagic fever and dengue shock syndrome, disproportionately afflict children and young adults. The primary goal of several vaccines now in development is to elicit protective neutralizing antibody responses; however, the exact definition of such responses remain unclear. Here, we review briefly the historical aspects of dengue vaccine development and current candidate dengue vaccines, and discuss various laboratory assays for gauging the neutralizing antibody responses to infection or vaccination, or both. We conclude that modification of current neutralization assays is required to improve the correlation between neutralization end point determinations and protection against secondary heterotypic dengue infections.