With dengue hemorrhagic fever, the blood vessels start to leak and cause bleeding from the nose, mouth, and gums. Bruising can be a sign of bleeding inside the body. Dengue hemorrhagic fever is fatal in about 5 percent of cases, mostly among children and young adults. The time between the bite of a mosquito carrying dengue virus and the start of symptoms averages 4 to 6 days, with a range of 3 to 14 days. An infected person cannot spread the infection to other persons but can be a source of dengue virus for mosquitoes for about 6 days.
Dengue is diagnosed by a blood test.
Anyone who is bitten by an infected mosquito can get dengue fever. Risk factors for dengue hemorrhagic fever include a person' s age and immune status, as well as the type of infecting virus. Persons who were previously infected with one or more types of dengue virus are thought to be at greater risk for developing dengue hemorrhagic fever if infected again. There is no specific treatment for dengue. Persons with dengue fever should rest and drink plenty of fluids.