Dengue viruses are transmitted by Aedes mosquitoes, which are most active during the day. Mosquitoes that transmit dengue usually are found near human dwellings and often are present indoors. Travelers are advised to use aerosol insecticides indoors and use bednets if sleeping quarters are not screened or air conditioned. Dengue fever is characterized by sudden onset, high fever, severe headaches, joint and muscle pain, nausea, vomiting and rash. The rash appears 3-4 days after the onset of fever.
Infection is diagnosed by a blood test that detects the presence of the virus or antibodies.
The illness may last up to 10 days, but complete recovery can take 2 to 4 weeks. Dengue is commonly confused with other infectious illnesses such as influenza, measles, malaria, typhoid and scarlet fever. Symptoms initially are indistinguishable from dengue fever, the illness progresses to faintness, shock, and generalized bleeding. See your physician if you become sick within a month of returning from travel in a tropical area. Be prepared to give your complete travel itinerary, so that the physician can evaluate the possibility that your symptoms were caused by a dengue infection.