What is dengue fever?
Dengue fever is a viral disease. It's spread by mosquitoes mainly in tropical and
subtropical areas of the world. It's rare in the continental U.S. But it's found in
some tropical U.S. territories such as Puerto Rico, Guam, and American Samoa. Dengue
fever is most common in:
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
How to say it
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 look like other diseases such
as the flu or malaria. The illness often lasts 3 to 7 days. Symptoms may include:
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 healthcare provider if you get sick within
a month of returning from travel in a tropical area. Your provider will ask you for
your complete travel history. Your provider can then figure out if your symptoms may
be a dengue infection.
How is dengue fever treated?
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 (nonsteroidal anti-inflammatory drug). In severe
cases, you may need medical care right away from healthcare providers familiar with
the disease. This can greatly cut the risk of death.
What are possible complications of dengue fever?
Severe dengue fever can be fatal if not treated right away. Other effects of severe
What can I do to prevent dengue fever?
There is an FDA-approved vaccine to prevent dengue fever in travelers. An FDA-approved
vaccine is available only for people ages 9 through 16 who have previous dengue fever
confirmed by a lab and who live in areas where dengue fever is common.
Travelers should prevent mosquito bites by:
Using DEET-based insect repellents on the skin and clothing
Using permethrin sprayed or soaked clothing as the Aedes mosquitoes bite during the
Staying in well-screened or air-conditioned areas
When should I call my healthcare provider?
Call your healthcare provider if you have fever within 3 weeks of travelling to an
area affected by the disease. Also call your healthcare provider right away if your
symptoms get worse or if you have new ones.
Key points about dengue fever
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's generally treated with pain medicine,
bed rest, and fluids.
When traveling to areas that have dengue fever, prevent mosquito bites. Use insect
repellents on skin and clothing.
Tips to help you get the most from a visit to your healthcare provider:
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
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
Know how you can contact your provider if you have questions.