Dengue

Who is at risk for infection with dengue virus?

• Anyone who travels to a tropical or subtropical region of the world, where dengue virus is found, is at risk for contracting dengue. 
• Typically younger children and those with their first dengue infection have a milder illness than older children and adults.    
• If you are sick with dengue, during the first week of infection, dengue virus can be found in your blood.  If a mosquito bites you during that time, it can become infected and then spread the virus to other people through bites. 
• In order to help prevent others from developing dengue, protect yourself from mosquito bites during the first week of illness--this involves resting in a screened or air-conditioned room or under a bed net while you have a fever.
• Dengue is common in the US territories of Puerto Rico, the US Virgin Islands, and American Samoa.
• Nearly all dengue cases reported in the 48 contiguous US states occurred in travelers infected elsewhere.
• Dengue outbreaks occasionally occur in the continental United States, most recently in Hawaii (2015), Florida (2013, 2020), and Texas (2013).
  • Most of these outbreaks have been small and limited in scope.
  • The mosquitoes that spread dengue are common throughout many areas of the United States, so local spread of dengue is possible should these mosquitoes bite an infected person.

What are the signs and symptoms of dengue?

• Approximately 1 in 4 people infected with dengue virus will get sick. 
• Symptoms of dengue can range from mild to severe.
• The most common symptoms include fever and one or more of the following:
  • severe headache
  • eye pain (typically behind the eyes)
  • muscle, joint, or bone pain
  • rash or unusual bleeding (nose or gums bleed, small red spots under the skin, or unusual bruising). 
• Symptoms typically begin 4-7 days after the mosquito bite and last for approximately 2-7 days. 

What are the signs of symptoms of severe dengue disease?

• About 1 in 20 people who get sick with dengue will develop severe dengue.
• If you have had dengue in the past, you are more likely to develop severe dengue.
• Infants and pregnant women are at high risk of developing severe dengue.
• The more severe forms of the disease, dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS), are characterized by a fever that lasts from 2 to 7 days, with one or more of the symptoms listed above. However, when the fever declines, the patient develops one or more of the following warning signs:

• severe abdominal pain
• persistent vomiting (at least 3 times in 24 hours)
• red spots or patches on the skin
• bleeding from the nose or gums
• vomiting blood or bloody or black/tarry stools
• drowsiness or irritability
• pale/cold/clammy skin, and/or difficulty breathing

• Severe dengue is a medical emergency. If any of these warning signs develop, go immediately to the emergency room.

How can I prevent dengue?

• The best prevention methods include avoiding mosquito bites.
• The mosquitoes that spread dengue are typically active and bite during the day.
• It is recommended to use insect repellents that contain DEET, picaridin, IR3535, oil of lemon eucalyptus, para-menthane-diol, or 2-undecanone.
  • Use the EPA's search tool to find the insect repellent that is right for you.
• In addition, use air conditioning or window/door screens and wear long-sleeved shirts and long pants or permethrin-treated clothing.
• Use bed nets when traveling overseas and sleeping outdoors or in a room that does not have screens.
• In order to help prevent mosquitoes from breeding in your yard, once a week, empty and scrub, turn over, cover, or throw out items that hold water, such as tires, buckets, planters, toys, or trash containers.

For people sick with dengue

• Caring for a sick family member (English), (Spanish)

Prevent mosquito bites in the U.S.

• Prevent mosquito bites (English), (Spanish)

Mosquito bite prevention for travelers

• Prevent mosquito bites while traveling (English), (Spanish)
• Areas with dengue around the world

Information for Healthcare Providers

• CDC:  Dengue Clinical Case Management Course
• CDC:  Dengue Vaccine:  What healthcare Professionals need to Know