In subtropical and tropical regions, the dengue virus represents a major threat to human health. The microorganism's natural hosts include mosquitoes, lower primates, and humans. Infection of the human host results in a biphasic fever with the potential to evolve into severe hemorrhagic disease. Over the past few decades, the virus genome structure, viral proteins, and viral antigens have been well characterized. Unfortunately though, the precise mechanisms by which the dengue virus causes disease remain unknown. Throughout history, major dengue fever epidemics have generally occurred at irregular intervals within the range of the mosquito vector. For instance, in 1922, one such epidemic may have affected between 1 and 2 million people in the southern United States. At present, dengue fever may cause more human morbidity and mortality than any other arthropod-borne viral disease (Henchal & Putnak, 1990, pp. 376-396). The dengue viruses are currently endemic in most tropical areas of the world (Lanciotti, Lewis, Gubler, & Trent, 1994, p. 65). It has been estimated that there could be as many as 100 million cases of dengue infection every year (Halstead, 1988, p. 476). The only natural hosts for dengue virus infections are mosquitoes, lower primates (e.g., chimpanzees, rhesus monkeys, and macaques), and humans.
Dengue fever is a flu-like viral disease common throughout the tropical and sub-tropical regions around the world, mainly in urban and peri-urban areas. Today, it afflicts an estimated 50 million to 100 million in the tropics (Epstein, 2000). The virus has four antigenically related serotypes, which are named DEN-1, DEN-2, DEN-3, and DEN-4. Each dengue serotype is a variation of the flavivrus genus. Dengue is spread by the aedes aegypti, a domestic, day-biting mosquito that prefers to bite humans. Currently, there is no vaccine available to prevent dengue.
Each type of the dengue virus is re-emerging worldwide, especially in the Western Hemisphere. Research has shown that several factors are contributing to the resurgence of dengue fever such as uncontrolled urbanization, increased international travel, substandard socio-economical conditions, and finally global warming. Global warming has shown to be a major contributor to the spread of dengue fever.
On a molecular level, dengue fever is classified as a flavivirus and appears as a spherical particle, about 40 to 50 nanometers in diameter
Dengue fever, also known as break bone fever, is an acute febrile infectious disease caused by the dengue virus. Typical symptoms include headache, a petechial rash, and muscle and joint pains; in a small proportion the disease progresses to life-threatening complications such as dengue hemorrhagic fever or dengue shock syndrome. Dengue is usually transmitted by the mosquito Aedes aegypti, and rarely Aedes albopictus. The virus has four different serotypes, and an infection with one usually gives lifelong immunity to it but only short-term immunity to the others. There is currently no available vaccine, but outbreaks can be prevented by reducing the habitat and number of mosquitoes, and limiting exposure to bites. Treatment of acute dengue is supportive, using either oral or intravenous rehydration for mild or moderate disease and blood transfusions for more severe cases. Rates of infection have increased dramatically over the last 50 years with approximate 50–100 million people being infected yearly. The disease has become global and is currently endemic in more than 110 countries with 2.5 billion people living in areas where it is prevalent.
The World Health Organization's 2009 classification divides dengue fever into two groups: uncomplicated and severe. This replaces the 1997 WHO classification, which was simplified as it was found to be too restrictive, but the older classification is still widely used. The 1997 classification divided dengue into...
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