Dengue fever: What you need to know about virus and symptoms
U.S. cases of dengue usually occur among travelers coming back from places like the Caribbean who bring it back to local mosquito populations.
The Centers for Disease Control and Prevention issued a health advisory Tuesday warning of an increase in dengue virus infections this year.
Dengue is a viral disease caused by any of the four dengue viruses, and is spread to people through mosquito bites. Up to 400 million people are infected by the virus each year.
From January 1 to June 24 of this year, countries in the Americas have reported more than 9.7 million dengue cases, the CDC said, twice as many as the 4.6 million cases reported in 2023.
With 1,489 cases reported, Puerto Rico has declared a health emergency, and the CDC says a higher-than-expected number of dengue cases have been identified among U.S. travelers this year as of June 24, or 745 cases.
Globally, dengue cases are also increasing, and the CDC recommends for healthcare providers, public health authorities and the public to have “increased suspicion” of dengue among people with a fever who have been in areas of frequent or continuous dengue transmission within 14 days before the illness onset.
Additionally, the CDC says to report dengue cases in a timely manner to public health officials and to promote mosquito bite prevention measures among people living in or visiting areas with frequent or continuous dengue transmission.
Here’s what to know about dengue.
Dengue is caused by four distinct but closely related dengue viruses: dengue virus 1, 2, 3 and 4. It is spread to people through the bite of an infected mosquito, and transmission is common in tropical and subtropical areas of the world.
Up to 400 million people are infected with a dengue virus every year, the CDC says.
About one in four people infected with dengue will get sick, according to the CDC, and for people who do get sick, symptoms can range from mild to severe.
Symptoms include:
Symptoms usually last 2-7 days, and most people recover within about a week.
There is no specific medicine to treat dengue, but the CDC recommends a dengue vaccine for U.S. territories and freely associated states.
Since dengue is spread through mosquito bites, you can help protect yourself by: