What You Should Know About Dengue Fever

Every year, 400 million people get the dengue virus and causes symptoms of dengue fever in 100 million people. People can get the dengue virus if the Aedes mosquito bites them. Luckily, the dengue virus doesn’t usually live in the U.S., so you don’t have to worry about getting it if you get bitten while at home. But in many countries, the dengue virus is endemic — which means it’s always around. If you’re traveling outside the U.S. — here’s what you should know about dengue fever. 

What is dengue fever/breakbone fever?

Dengue fever, also known as breakbone fever, is an illness caused by dengue virus. Not everyone who gets the dengue virus will get sick. Only about 25% of people with the virus actually have any symptoms. The most common symptoms people have are:

• Fever (which can be as high as 104°F)

• Severe bone or joint pain

• Rash

• Body aches

• Pain behind the eyes

• Nausea and vomiting

Most people only have mild or moderate symptoms that last between 2 and 7 days. But some people (under 1%) with dengue fever can develop severe symptoms that can be life-threatening. Severe disease is more common in:

• Infants and children

• People who are immunocompromised

• People who are pregnant

How does dengue fever spread?

The Aedes mosquito gets the virus from biting people who have dengue. The mosquito can carry the dengue virus and not get sick from it. When the mosquito bites a person, it passes the virus to that person’s bloodstream. So people and mosquitoes are constantly passing dengue virus back and forth. As long the mosquitos are around, so is the dengue virus.

Where is dengue fever commonly found? 

The Aedes mosquito lives in warm, tropical places all over the world — including many countries in Southeast Asia, Central Africa, Oceania/Pacific Islands, and the Americas. Countries in the Americas where dengue virus is almost always actively passing between humans and mosquitoes include:

• Puerto Rico and the U.S. Virgin Islands

• Most Caribbean nations, except Anguilla, Bermuda, and Montserrat

• Nations in Central America, except parts of Mexico

• Most nations in South America, except parts of Argentina, Ecuador, Peru, and Uruguay

Though the dengue virus is not usually found in the U.S. — cases have happened because the Aedes mosquito can live in certain parts of the country. Cases of dengue have been reported in Hawaii, Texas, Florida, and the Florida Keys.

How can I lower my chances of getting dengue fever?

If you are traveling outside of the U.S., especially to warmer climates, you should take precautions to keep yourself from getting mosquito bites. 

Use mosquito repellent

It’s best to use mosquito repellents that the Environmental Protection Agency (EPA) has approved. Check the active ingredient on the back of your repellent to make sure it has one of the following:

• DEET (up to 30%)

• Oil of lemon eucalyptus (OLE)

• Picaridin

• 2-undecanone

• Para-menthane-diol (PMD)

Make sure to apply repellent on exposed skin surfaces whenever you go outside. Mosquitos are active during the morning and the daytime — not just at night.

If you have children, keep in mind that OLE and PMD are not safe for kids younger than 3 years old. And there are no approved insect repellents for children younger than 2 months old. 

Keep yourself covered 

If possible, wear long sleeves and pants when you’re outside. You can spray your clothes and gear with mosquito repellent, too. 

At night, use mosquito nets over your bed. If you can, keep doors and windows closed. If that’s not an option, a screen covering is also helpful. But make sure screens over windows, doors, and porches are in place and free of breaks or rips.

You can also place mosquito netting over cribs and strollers to keep babies safe. Make sure the netting is properly attached so it doesn’t come loose and become a strangulation hazard. 

Drain standing water

Mosquitoes lay their eggs in standing water — and it doesn’t take much water either. A single mosquito can lay hundreds or thousands of eggs in even a small puddle. Look around where you’re staying and:

• Empty standing water from plastic pools, toys, buckets, flower pots, or other outdoor containers where rain or sprinkler water can collect. 

• Empty birdbaths and pet water bowls a few times a week. 

• Don’t let water collect in tarps over pools and boats. 

• Keep pools chlorinated properly so mosquitoes can’t lay their eggs in your pool. 

What should I do if I think I have dengue fever?

Symptoms from dengue fever typically start 4 to 10 days after a mosquito bite. If you think you could have dengue fever, go see your healthcare provider. Make sure you let your healthcare provider know if you were recently in an area where dengue fever is common. They can send a blood test to the lab to look for the virus. 

There’s no treatment that can cure dengue fever. Symptoms usually last 2 to 7 days. In the meantime, the following things can help you feel better:

• Get some rest

• Drink fluids 

• Use acetaminophen (Tylenol) or ibuprofen for fever and pain

Young children and people who are pregnant are more likely to get severe symptoms and will need to be followed more closely by their healthcare providers.