Dengue (pronounced den'-ghee) fever is a leading cause of illness and death in the tropics and subtropics, with more than one-third of the world's population living in areas at risk for transmission.
Dengue fever is caused by any one of four related viruses (DENV 1, DENV 2, DENV 3, and DENV 4) transmitted by mosquitoes. In the Western Hemisphere, the Aedes aegypti mosquito is the most important vector (transmitter) of dengue viruses. However, in 2001, an outbreak in Hawaii was found to be transmitted by the Aedes albopictus mosquito. Currently, there are no preventive dengue virus vaccines and no specific medications to treat a dengue infection. Since dengue fever is a mosquito-transmitted infection, prevention and protection against bites is essential. Early detection and rapid response can reduce the severity of the infection.
As many as 100 million people are infected yearly. In 2007, a total of 900,782 cases of dengue fever were reported in the Americas, with 26,413 cases of dengue hemorrhagic fever. According to the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO), outbreaks were reported in 11 countries.
Dengue fever has been a worldwide problem since the 1950s. Occurring rarely in the continental United States, dengue fever is endemic in Puerto Rico and in many popular tourist destinations in Latin America and Southeast Asia. There have been periodic outbreaks in Samoa and Guam. Other locations of outbreaks include northern Argentina, northern Australia, the entirety of Bangladesh, Barbados, Bolivia, Belize, Brazil, Cambodia, Costa Rica, the Dominican Republic, El Salvador, Guatemala, Guyana, Honduras, India, Indonesia, Jamaica, Laos, Malaysia, Mexico, Micronesia, Panama, Paraguay, Philippines, Puerto Rico, Singapore, Sri Lanka, Suriname, Taiwan, Thailand, Trinidad, Venezuela, and Vietnam, and increasingly in southern China.
Arbovirus infections, breakbone fever, circulatory collapse, dengue hemorrhagic fever, dengue infection, dengue shock syndrome, dengue virus, DENV, DENV 1, DENV 2, DENV 3, DENV 4, DF, DHF, DSS, epidemic, Flaviviridae, Flaviviridae infections, Flavivirus, RNA virus infections.
types of the disease
Dengue hemorrhagic fever (DHF) is a severe form of dengue infection caused by the same viruses that cause dengue fever. It is characterized by thrombocytopenia (abnormally low platelets) and hemoconcentration (decreased fluid content in the blood; grades I and II) and is distinguished by a positive tourniquet test (the appearance of small hemorrhages (bleeding from ruptured blood vessels) or petechiae (small red dots caused by broken blood vessels) on the skin after the application of a tourniquet or blood pressure cuff). If unrecognized or left untreated, DHF can be fatal. With proper treatment, the Centers for Disease Control and Prevention (CDC) estimates a mortality rate of less than 1%.
When accompanied by circulatory failure and shock (grades III and IV), DHF is called dengue shock syndrome (DSS).
As there is no cross-immunity or form of competitive interference between strains, it is possible to have DF four times, once from each DF virus.