What is dengue fever?

Dengue (pronounced DEN-gee) fever is a viral disease. It is transmitted by mosquitoes, mainly in tropical and subtropical areas of the world. The disease is most common in:

• South Pacific
• South Central Asia
• Caribbean
• Central and South America
• Africa

Dengue fever happens most often in urban areas. But it may be found in rural areas. The mosquitoes that carry the virus usually pass it on during and shortly after the rainy season. The mosquitoes are most active during the day. They are found near human dwellings, often indoors. About half of the world's population is now at risk for this disease.

What causes dengue fever?

Dengue fever is caused by a virus. A certain type of mosquito (Aedes) passes the virus to people through its bites.

What are the symptoms of dengue fever?

Dengue fever causes a severe flu-like illness. It may be look like other diseases such as the flu or malaria. The illness usually lasts three to seven days. Symptoms may include:

• Sudden high fever
• Severe headaches
• Pain behind the eyes
• Joint and muscle pain
• Nausea
• Vomiting
• Swollen glands
• Rash that appears three to four days after the fever starts

A very small portion of people with dengue fever get a severe case. It’s called dengue hemorrhagic fever. Symptoms show up as the fever begins to ease. These may include vomiting that does not go away, rapid breathing, blood in vomit, and bleeding gums.

How is dengue fever diagnosed?

A special blood test can diagnose dengue fever. It can find the virus or antibodies made in response to the virus. See your doctor if you get sick within a month of returning from travel in a tropical area. Your doctor will ask you for your complete travel history. He or she can then figure out if your symptoms may be a dengue infection.

How is dengue fever treated?

Your doctor will figure out the best treatment for you based on:

• How old you are
• Your overall health and past health
• How sick you are
• How well you can handle specific medicines, procedures or therapies
• How long the condition is expected to last
• Your opinion or preference

Dengue fever is generally treated with supportive care such as pain relievers, bed rest and fluids. You may take acetaminophen to lower the fever. But you should not take aspirin, ibuprofen or any NSAID (non-steroidal anti-inflammatory drug). In severe cases, you may need medical care right away from health-care providers familiar with the disease. This can greatly cut the risk of death.

What are the complications of dengue fever?

Severe dengue fever can be fatal if not treated right away. Other effects of severe dengue are:

• Severe bleeding
• Breathing problems
• Organ damage

How can dengue fever be prevented?

There is no widely used or FDA-approved vaccine for dengue fever. Travelers should avoid mosquito bites by:

• Using DEET-based insect repellents on the skin and clothing
• Using permethrin-sprayed clothing as the Aedes mosquitoes bite during the daytime hours
• Staying in well-screened or air-conditioned areas

When should I call my doctor?

Call your doctor if you have fever within three weeks of travelling to an area affected by the disease. Also call your doctor right away if your symptoms get worse or you have new ones.

Key Points

• Dengue fever is caused by a virus passed on by the bite of a daytime biting mosquito.
• Dengue fever occurs in tropical and subtropical areas of the world.
• The disease causes a severe flu-like illness. It is generally treated with bed rest and fluids.
• When traveling to areas that have dengue fever, avoid mosquito bites. Use insect repellents on skin and clothing.

Next Steps

Tips to help you get the most from a visit to your doctor:

• Know the reason for your visit and what you want to happen.
• Before your visit, write down questions you want answered.
• Bring someone with you to help you ask questions and remember what your provider tells you.
• At the visit, write down the name of a new diagnosis, and any new medicines, treatments or tests. Also, write down any new instructions your provider gives you.
• Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
• Ask if your condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if you do not take the medicine or have the test or procedure.
• If you have a follow-up appointment, write down the date, time and purpose for that visit.
• Know how you can contact your doctor if you have questions.