Dengue Gaining Ground

Abstract

The dengue viruses, enveloped positive-sense RNA viruses with a genome of approximately 11 kb, and consisting of four related but anti genetically distinct serotypes, cause the most common arthropod-borne viral disease in man. In most cases, dengue virus infection is asymptomatic, but can potentially cause an acute febrile disease ranging in severity from classical dengue fever to a life-threatening hemorrhagic condition with shock syndrome. Its mode of transmission is by the mosquito species Aedes aegypti and Aedesalbopictus, both species notoriously known as intermittent feeders of human blood, and with ecological niches well-adapted to human habitation [2]. It has been assumed for many years that there are approximately one hundred million dengue infections per year, but recent estimate indicates 390 million per year, of which 96 million manifests clinically [3]. Still, there are no anti-viral drugs against dengue disease, and neither prophylaxis nor vaccines exist. An effective dengue virus vaccine would need to provide a balanced immune response against all four serotypes. This has proven difficult to achieve despite considerable efforts. A number of dengue vaccines candidates are in pipeline, but it remains to be seen when there will be a well-tolerated and effective vaccine licensed and available on the market [2].