Dengue Fever

What is dengue?

Dengue (say "DEN-gay") is a viral infection spread to humans by mosquitoes. Mild cases cause a rash and flu-like symptoms. Some people, such as infants and those with other health problems, can get more severe types of the disease.

How is it spread?

Dengue is spread through the bite of mosquitoes that carry the virus. The virus cannot spread from person to person through casual contact. People who have dengue need to be protected from getting more mosquito bites. If a mosquito bites an infected person, the mosquito becomes infected with the virus and can then pass it to other people.

Outbreaks are common in many countries in Latin America and Southeast Asia. The disease also occurs in Africa, parts of the Middle East, the Western Pacific, Puerto Rico, and other tropical and subtropical areas. Travelers visiting these regions may be at risk of getting infected.

Dengue is rare in the United States.

What are the symptoms?

Symptoms of dengue may be mild or severe. In mild cases, common symptoms include:

• A sudden high fever.
• A headache.
• Eye pain.
• Joint and muscle pain.
• A rash.
• Nausea, vomiting, and loss of appetite.

The fever usually lasts up to a week and may come and go.

After the initial fever, some people may have more serious symptoms and need medical treatment right away. These symptoms can include:

• Signs of bleeding, such as:
  • Red patches that may look like bruises or tiny red spots.
  • Bleeding from the nose, mouth, or gums.
  • Vomiting blood.
  • Stools that look like black tar.
• Severe belly pain.
• Signs of shock.

How is it diagnosed?

Your doctor will ask about your symptoms and any recent travel. The doctor may order a blood test to confirm whether you have dengue.

How is dengue treated?

There is no medicine for treating dengue. Mild cases may be treated at home with rest and plenty of fluids to prevent dehydration. You may take acetaminophen (Tylenol) for pain. But don't take anti-inflammatory medicines like aspirin, ibuprofen (such as Advil or Motrin), or naproxen (such as Aleve). They may increase the risk of bleeding. Be safe with medicines. Read and follow all instructions on the label. People with mild infections of dengue usually feel better within 2 weeks.

More serious infections usually require treatment in a hospital. You may need intravenous (I.V.) fluids to treat dehydration. You also may need a blood transfusion to replace lost blood. You will be closely watched for signs of shock.

How can you help prevent it?

A vaccine for dengue is available in some parts of the world. You can talk to your doctor about whether the dengue vaccine is right for you. People can get dengue more than once.

You can do things to help protect yourself from mosquito bites when you travel.

• Wear long pants and long-sleeved shirts. Some outdoor-clothing stores sell clothing already treated with insect repellent.
• Use insect repellent recommended by the Environmental Protection Agency (EPA).
  • Use one with DEET, picaridin, IR3535, oil of lemon eucalyptus, paramenthane-diol, or 2-undecanone. You can get repellents in different strengths. Read and follow all instructions on the label, especially for how to use them on children.
  • Spray clothing with DEET. Mosquitoes may bite through thin clothing. (Remember that DEET can damage plastic, such as watch crystals, eyeglass frames, and some synthetic fabrics.)
• Sleep under bed nets (mosquito netting).
• Use flying-insect spray indoors around sleeping areas.

To learn more

The most current information about dengue is available from the U.S. Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO). If you are planning international travel, you can learn about the risk of dengue in the area you're traveling to by:

• Visiting the CDC website at www.cdc.gov/dengue or by calling their toll-free phone number (1-800-232-4636).
• Contacting your doctor or local health department.