Dengue (DENG-gey) fever is a mosquito-borne disease that occurs in tropical and subtropical areas of the world. Mild dengue fever causes a high fever, rash, and muscle and joint pain. A severe form of dengue fever, also called dengue hemorrhagic fever, can cause severe bleeding, a sudden drop in blood pressure (shock) and death.
Millions of cases of dengue infection occur worldwide each year. Dengue fever is most common in Southeast Asia and the western Pacific islands, but the disease has been increasing rapidly in Latin America and the Caribbean.
Researchers are working on dengue fever vaccines. For now, the best prevention is to reduce mosquito habitat in areas where dengue fever is common.
Symptoms:
Many people, especially children and teens, may experience no signs or symptoms during a mild case of dengue fever. When symptoms do occur, they usually begin four to seven days after you are bitten by an infected mosquito.
Dengue fever causes a high fever — 104 F degrees — and at least two of the following symptoms:
• Headache
• Muscle, bone and joint pain
• Nausea
• Vomiting
• Pain behind the eyes
• Swollen glands
• Rash
Most people recover within a week or so. In some cases, symptoms worsen and can become life-threatening. Blood vessels often become damaged and leaky. And the number of clot-forming cells (platelets) in your bloodstream drops. This can cause a severe form of dengue fever, called dengue hemorrhagic fever, severe dengue or dengue shock syndrome.
Signs and symptoms of dengue hemorrhagic fever or severe dengue — a life-threatening emergency — include:
• Severe abdominal pain
• Persistent vomiting
• Bleeding from your gums or nose
• Blood in your urine, stools or vomit
• Bleeding under the skin, which might look like bruising
• Difficult or rapid breathing
• Cold or clammy skin (shock)
• Fatigue
• Irritability or restlessness
Causes:
Dengue fever is caused by any one of four types of dengue viruses spread by mosquitoes that thrive in and near human lodgings. When a mosquito bites a person infected with a dengue virus, the virus enters the mosquito. When the infected mosquito then bites another person, the virus enters that person's bloodstream.
After you've recovered from dengue fever, you have immunity to the type of virus that infected you — but not to the other three dengue fever virus types. The risk of developing severe dengue fever, also known as dengue hemorrhagic fever, actually increases if you're infected a second, third or fourth time.
Risk factors:
Factors that put you at greater risk of developing dengue fever or a more severe form of the disease include:
• Living or traveling in tropical areas: Being in tropical and subtropical areas increases your risk of exposure to the virus that causes dengue fever. Especially high-risk areas are Southeast Asia, the western Pacific islands, Latin America and the Caribbean.
• Prior infection with a dengue fever virus: Previous infection with a dengue fever virus increases your risk of having severe symptoms if you're infected again.
Diagnoses:
Diagnosing dengue fever can be difficult, because its signs and symptoms can be easily confused with those of other diseases — such as malaria, leptospirosis and typhoid fever.
Your doctor will likely ask about your medical and travel history. Be sure to describe international trips in detail, including the countries you visited and the dates, as well as any contact you may have had with mosquitoes.
Certain laboratory tests can detect evidence of the dengue viruses, but test results usually come back too late to help direct treatment decisions.
Treatment:
No specific treatment for dengue fever exists. Your doctor may recommend that you drink plenty of fluids to avoid dehydration from vomiting and a high fever.
While recovering from dengue fever, watch for signs and symptoms of dehydration. Call your doctor right away if you develop any of the following:
• Decreased urination
• Few or no tears
• Dry mouth or lips
• Lethargy or confusion
• Cold or clammy extremities
