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Dengue: What you need to know

The risk of this infection is low in the United States. But health officials have reason to believe the problem may become more common here in the future.

Many Americans haven't even heard of it. But dengue (pronounced "DEN-gee") is a serious illness that is making inroads into the United States.

Previously, the mosquito-borne virus was mostly seen in tropical areas. But, according to the Centers for Disease Control and Prevention (CDC), more than 1,200 cases were reported in the United States in 2019 and more than 300 in 2020. And a type of mosquito that transmits the disease does live here, especially in southern states. The amount of dengue-related illness in the United States is currently minimal. But since the disease usually follows the presence of such mosquitoes, there's a chance that dengue infection could spread, the National Institutes of Health (NIH) warns. People also may be at risk if they travel to areas where dengue is common.

Fortunately, there are steps people can take to reduce the risk of serious problems due to the disease.


Dengue is transmitted when an infected Aedes mosquito bites a human. Except in rare cases, the virus doesn't spread from person to person.

Many people who get infected have no symptoms or just a mild fever. However, other people may develop high fever, severe headaches, joint pain, backache, nausea, vomiting, eye pain and skin rash.

According to the CDC, some people also may develop dengue hemorrhagic fever (DHF), which can cause fever lasting two to seven days, nausea, headache, bruising, and bleeding from the nose and gums.

If not treated, DHF could cause serious health problems, including failure of the circulatory system and death, warns CDC.


While there is no specific medicine to treat dengue and DHF, physicians can treat symptoms and replace lost fluids. Pain relievers can help treat headaches.

In severe cases, a person may need to be hospitalized, reports CDC.


You can take these steps to reduce your risk:

  • Cover or discard outdoor items that collect water, such as wading pools, buckets and old tires. This will discourage mosquitoes from laying eggs.
  • Make sure doors and windows are screened to keep mosquitoes out of your home.
  • Wear long sleeves and pants when outdoors.
  • Use insect repellent containing the chemical DEET.

There is no vaccine for people who have never been infected with a dengue virus. In 2019, the U.S. Food and Drug Administration approved a dengue vaccine for use in children 9 to 16 years old, but only if they live in an area where dengue is common—currently only American Samoa, Puerto Rico or the U.S. Virgin Islands—and only if they have a prior, laboratory-confirmed dengue virus infection.

If you have concerns

The risk of dengue is still quite low in the United States, but be sure to contact your doctor if you have any reason to believe you might be infected.

Reviewed 3/15/2021

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