Dengue Fever

Reviewed/Revised Feb 2024
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What is dengue?

Dengue is a viral infection spread by mosquitoes. A more serious version of the disease, called dengue hemorrhagic fever, causes bleeding and can be deadly.

  • Dengue is most common in the tropics and subtropics, such as Southeast Asia, Central and South America, and the Caribbean

  • You can get dengue if you're bitten by an infected mosquito

  • Symptoms include fever, headache, and body aches

  • You can get dengue more than one time

  • If you're traveling to an area with dengue, you should take steps to prevent mosquito bites

What causes dengue?

Dengue is caused by the dengue virus. This virus is in most tropical and subtropical parts of the world. It's most common in Southeast Asia and the Caribbean. But a few people have gotten dengue in the southern United States and Hawaii.

When a mosquito bites an infected person, it picks up the virus and gives it to the next person it bites.

What are the symptoms of dengue?

For 2 to 3 days, you'll feel weak and tired and have:

  • High fever and chills

  • Severe headache

  • Pain when you move your eyes

  • Severe aching pain in your back, legs, and joints—these are so painful that dengue was nicknamed “breakbone fever”

  • Rash on your face

After you have these symptoms, you may feel better for a day, and then the fever and rash may come back, this time on your chest, back, arms, and face.

In more severe cases, people may feel weak for several weeks, but it's rare to die from dengue fever.

What is dengue hemorrhagic fever?

Dengue hemorrhagic fever is a much more severe type of dengue. It mainly affects children younger than 10 years old in areas where dengue is common.

If you have dengue hemorrhagic fever, you have dengue symptoms and also:

  • Bleeding from your nose, mouth, rectum, and any puncture wounds

  • Pain in your belly

  • Throwing up blood

  • Blood in your stool or in urine

  • Purple spots on your skin from bleeding under your skin

  • Very low blood pressure (shock)

Go to the hospital right away if you have symptoms of dengue hemorrhagic fever.

How can doctors tell if I have dengue?

Doctors suspect dengue based on your symptoms and if you've been in an area where mosquitoes carry the infection. To know for sure, they’ll do blood tests.

How do doctors treat dengue?

There's no medicine to kill the dengue virus. Doctors will:

  • Give you IV fluids (into your vein), especially if you have dengue hemorrhagic fever

Doctors will keep you under mosquito nets while you're sick so mosquitoes don't pick up the infection from you and spread it to other people.

How can I prevent dengue?

If you live in or visit an area with dengue, take steps to prevent mosquito bites:

  • Spray your skin with a DEET (diethyltoluamide) bug spray

  • Use mosquito nets

  • Wear long-sleeved shirts and long pants

  • Put in window screens and repair any holes

  • Get rid of standing water in and near the home where mosquitoes multiply

In the United States, a dengue vaccine is approved for use in children who

  • Are 9 to 16 years old

  • Have had dengue previously, and

  • Live in an area where dengue is endemic (occurs frequently or continuously)

In the United States, endemic areas include some territories and freely associated states, such as Puerto Rico. The vaccine is not approved for travelers who are visiting but not living in an area where dengue is common. The vaccine is also available in Mexico, Brazil, Thailand, and some other countries.

Another dengue vaccine is being evaluated in the United States and is already approved for use in Indonesia, the European Union, and the United Kingdom. This vaccine can be used for people who have not had prior dengue infections as well as those who have. Several other dengue vaccines are under investigation.

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