Dengue (pronounced DENgee) fever is a painful, debilitating mosquito-borne disease caused by any one of four closely related dengue viruses. These viruses are related to the viruses that cause West Nile infection andyellow fever.An estimated 390 dengue infections occur worldwide each year, with about 96 million resulting in illness. Most cases occur in tropical areas of the world, with the greatest risk occurring in:*.The Indian subcontinent*.Southeast Asia*.Southern China*.Taiwan*.The Pacific Islands*.The Caribbean (except Cuba and the Cayman Islands)*.Mexico*.Africa*.Central and South America (except Chile, Paraguay, and Argentina)Most cases in the United States occur in people who contracted the infection while traveling abroad. But the risk is increasing for people living along the Texas-Mexico border and in other parts of the southern United States. In 2009, an outbreak of dengue fever was identified in Key West, Fla.Dengue fever is transmitted by the bite of an Aedes mosquito infected with a dengue virus. The mosquito becomes infected when it bites a person with dengue virus in theirblood. It can’t be spread directly fromone person to another person.Symptoms of Dengue FeverSymptoms, which usually begin four to six days after infection and last for up to 10 days, may include*.Sudden,high fever*.Severeheadaches*.Pain behind theeyes*.Severe joint andmuscle pain*.Fatigue*.Nausea*.Vomiting*.Skin rash, which appears two to five daysafter the onset of fever*.Mild bleeding (such a nose bleed,bleeding gums, or easy bruising)Sometimes, symptoms are mild and can bemistaken for those of thefluor anotherviral infection. Younger children and people who have never had the infection before tend to have milder cases than olderchildren and adults. However, serious problems can develop. These include dengue hemorrhagic fever, a rare complication characterized byhigh fever,