OVERVIEW
Dengue fever is an illness spread by the bite of mosquitos infected with one of the dengue viruses. Symptoms are usually flu-like but can worsen to severe dengue (dengue hemorrhagic fever), a life-threatening condition. Getting infected a second time increases your risk of serious symptoms.
What is Dengue Fever?
Dengue fever is an illness you can get from the bite of a mosquito carrying one of four types of dengue virus (DENV). The virus is most commonly found in tropical and subtropical regions, including Central and South America, Africa, parts of Asia and the Pacific Islands.
Dengue isn’t contagious from person to person except when passed from a pregnant person to their child. Symptoms are usually mild with your first infection, but if you get another infection with a different version of DENV, your risk of severe complications goes up.
Who does Dengue Fever Affect?
Dengue is most commonly found in Central and South America, Africa, parts of Asia and the Pacific Islands. A few parts of the U.S. also have dengue. Those living in or traveling to these regions — more than half the people in the world — are most at risk. Children and those who are elderly are at higher risk for serious illness.
Causes
Dengue fever is caused by one of four dengue viruses. When a mosquito infected with the dengue virus bites you, the virus can enter your blood and make copies of itself. The virus itself and your immune system’s response can make you feel sick.
The virus can destroy parts of your blood that form clots and give structure to your blood vessels. This, along with certain chemicals that your immune system creates, can make your blood leak out of your vessels and cause internal bleeding. This leads to the life-threatening symptoms of severe dengue.
Symptoms
- High fever
- Severe headache
- Pain behind the eyes
- Muscle and joint pain (dengue is often called “breakbone fever”)
- Skin rash
- Nausea and vomiting
- Mild bleeding (nose or gums)
Severe dengue may include:
- Abdominal pain
- Persistent vomiting
- Bleeding under the skin or from orifices
- Difficulty breathing
Diagnosis
- Blood Tests: Detect dengue virus antigens (NS1 test) or antibodies (IgM/IgG).
- Complete Blood Count (CBC): Monitors platelet levels and white blood cell count.
- Physical Examination: Evaluates symptoms and checks for complications.