Dengue Virus

Classification

Group: Group IV ((+)ssRNA)

Family: Flaviviridae

Genus: Flavivirus

Species: Dengue Virus

The Dengue Virus, pronounced as [deng – gey or deng – gee] is a category-A pathogen and therefore is a serious threat to the human population globally. Category A pathogens are microbes that are hazardous to lab personnel and have the potential to cause serious epidemic disease. The Dengue Virus has four different serotypes, DEN-1, DEN-2, DEN-3 and DEN-4. These four serotypes are approximately 60-80% homologous but different enough to restrict cross immunity. This means that if a person is infected with one type of the four Dengue virus serotypes, they will build immunity to that specific serotype, but not for the other three. This lack of cross immunity is what poses a problem in the development of a vaccine for Dengue. The Dengue virus causes a less lethal condition known as Dengue Fever, which is also known as the breakbone fever. The Dengue virus causes a more lethal condition in some who are infected and that is known as the Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DHS).

The Dengue virus is currently believed to be the most common mosquito-borne disease in recent times and cause for increased international health concerns. The Dengue virus currently poses a risk to approximately 2.5 billion people of the worlds total population. In other words, almost one third of the world is at risk for this potentially deadly virus. The Dengue virus is transmitted amongst humans via its main vector, the Aedes aegypti mosquito. This virus is mostly found in countries along the equator and in countries with tropical and subtropical conditions because these are the conditions needed for this mosquito to thrive in. The mosquito acquires the disease from an infected individual and then carries it and passes it on to other individuals it feeds off of. Once an individual has been infected the virus then causes the person to come down with Dengue Fever. Dengue fever is a febrile disease and has Flu like symptoms accompanied by a rash and severe aches and pains. Headaches are extremely common and stronger than normal. Joint pain is also very common. Dengue Fever will usually subside in approximately five to ten days. Dengue Hemorrhagic Fever is the more serious complication caused by the Dengue Virus. Dengue Hemorrhagic Fever has an incubation period that is similar to Dengue Fever (approximately 3-5 days) but unless treated with a combination of corticosteroids, proper hydration and physician supervision, DHF will be mortal for the individual. Dengue Hemorrhagic Fever causes the blood vessels to become excessively permeable accompanied by thrombocytopenia and abnormal hemostasis.