Dengue (pronounced den' gee) is a disease caused by any one of four closely related dengue viruses (DENV 1, DENV 2, DENV 3, or DENV 4). 

The dengue viruses are transmitted to humans by the bite of an infected mosquito. In the Western Hemisphere, the Aedes aegypti mosquito is the most important transmitter of dengue viruses, although a 2001 outbreak in Hawaii was transmitted by Aedes albopictus. 

The principal symptoms of dengue are a high fever that lasts 2-7 days and at least two of the following:

• Severe headache
• Severe eye pain (behind eyes)
• Joint pain
• Muscle and/or bone pain
• Rash
• Mild bleeding manifestation (e.g., nose or gum bleed, petechiae, or easy bruising)
• Low white cell count

Go IMMEDIATELY to an emergency room or the closest health care provider if any of the following warning signs appear:

• Severe abdominal pain or persistent vomiting
• Red spots or patches on the skin
• Bleeding from nose or gums
• Vomiting blood
• Black, tarry stools (feces, excrement)
• Drowsiness or irritability
• Pale, cold, or clammy skin
• Difficulty breathing

Outbreaks of dengue occur primarily in areas where Aedes aegypti (sometimes also Aedes albopictus) mosquitoes live. This includes most tropical urban areas of the world. Dengue viruses may be introduced into areas by travelers who become infected while visiting other areas of the tropics where dengue commonly exists.

Anyone who is living in or traveling to an area where the virus is found is at risk for infection.

There is no specific medication for treatment of a dengue infection. Persons who think they have dengue should use analgesics (pain relievers) with acetaminophen and avoid those containing aspirin. They should also rest, drink plenty of fluids, and consult a physician. If they feel worse (e.g., develop vomiting and severe abdominal pain) in the first 24 hours after the fever declines, they should go immediately to the hospital for evaluation.

As with dengue fever, there is no specific medication for DHF. It can however be effectively treated by fluid replacement therapy if an early clinical diagnosis is made. DHF management frequently requires hospitalization. 

There is no vaccine available against dengue, and there are no specific medications to treat a dengue infection. This makes prevention the most important step, and prevention means avoiding mosquito bites if you live in or travel to an endemic area. 

Dengue rarely occurs in the continental United States, but it is endemic in Puerto Rico and in many popular tourist destinations in Latin America, Southeast Asia and the Pacific islands.