New data shows where cases of deadly ‘breakbone’ fever are rising across the US.
Dengue fever, a mosquito-borne virus that causes excruciating headaches and joint pain, has ravaged Florida with 485 cases so far this year, according to the Centers for Disease Control and Prevention (CDC)’s latest figures.
This is up 93 from 392 only a week prior, making the outbreak the largest on record in Florida’s history.
The outbreak has led multiple Florida counties to declare states of emergency to control the spread, which can be in effect for seven days unless officials extend or rescind them.
But new CDC data released last week shows more than a dozen other states are seeing surges in dengue fever.
Since September 21, dengue cases have increased in Florida, New York, Texas, New Jersey, Illinois, Washington, Maryland, Connecticut, Massachusetts, Kentucky, Indiana, Nebraska, Colorado and West Virginia.
Experts are unsure of the specific culprit behind the nationwide outbreak, but they suspect it may be due to international travel and the expanding presence of Aedes mosquitoes across the US.
The CDC has also issued level one travel advisories for Cuba, Ecuador and Panama due to the countries ‘reporting increased numbers of cases’ of dengue, which causes outbreaks every two to five years.
Dengue fever spreads through the bite of infected Aedes mosquitoes, mainly the Aedes aegypti (pictured above), a species commonly found in Florida
A level one notice is the lowest level of the CDC’s four classes. It does not discourage travel but urges people visiting these countries to ‘practice usual precautions.’
Dengue fever can be prevented by using insect repellent and long, protective clothing to avoid mosquito bites. Eliminating standing water by dumping it out of buckets, pet dishes and roof gutters also prevents mosquitoes from laying eggs.
Additionally, the CDC recommends using screens on windows and doors or staying in air-conditioned rooms.
Other countries with level one advisories for dengue are Bangladesh, Bolivia, Cambodia, Colombia, Costa Rica, Kenya, Malaysia, Maldives, Marshall Islands, Sri Lanka, Vanuatu and Vietnam.
There have been 2,145 reported cases of dengue so far this year in the US. Of those, 79 percent were confirmed and 21 percent were probable. A total of 1,590 cases were locally acquired while 555 were associated with international travel.
A CDC report from earlier this year showed there was a 359 percent rise in average annual dengue cases in the US in 2024 compared to the 2010-2023 annual average.
In 2024, the most recent data available in the report, a record 3,798 dengue fever cases were reported, an increase from the average of 828. Among the cases, 97 percent were travel-associated and the remaining three percent, 105 cases, were locally acquired.
Dengue is often called ‘breakbone fever’ because patients who get sick with the virus typically develop a sudden high fever along with a pounding headache, pain behind the eyes and deep aches in the muscles, joints and bones.
It isn’t native to Florida, or any other area in the US, but the state’s warm and humid climate makes it an ideal setting for mosquitoes that carry the disease.
Since September 21, Florida and 13 other states have seen increases in reported dengue cases. New York saw an increase from 27 to 31, while cases in Texas went up from 14 to 17.
Cases increased from 16 to 19 in New Jersey and from 10 to 13 in Illinois, while Washington state saw two additional cases, increasing its total to 18.
Maryland, Connecticut, Massachusetts, Kentucky, Indiana, Nebraska and Colorado all reported one additional case. Maryland now has 12, Connecticut has seven, Massachusetts and Colorado each have 11, Kentucky has five and Indiana and Nebraska each have three.
West Virginia also reported its first case.
Cuba has recorded 11,235 cases so far this year, more than nine times higher than average, according to the Global Dengue Observatory.
In Ecuador, local health authorities have confirmed 32,576 cases and 35 deaths so far this year. The country reported 37,840 cases and 65 deaths last year.
Panama’s Ministry of Health reports 9,055 cases and 19 deaths thus far in 2026 compared to about 15,600 illnesses and 28 deaths last year.
Dengue fever often causes an asymptomatic infection, but in some patients it can trigger life-threatening internal bleeding, respiratory distress and heart failure.
It can also lead to shock and organ failure, especially of the liver, brain and heart.
Health officials say about 40 to 80 percent of people infected with dengue fever do not develop any symptoms, but if symptoms do develop, they appear abruptly about five to seven days after infection.
Warning signs include a fever above 100F (38C), severe headache, pain behind the eyes, bone, joint or muscle pain, and bleeding in the gums.
Some patients also develop redness of the skin on the face within the first 24 to 48 hours of symptoms emerging.
In severe cases, patients may also suffer from severe abdominal pain, persistent vomiting and lethargy.
Patients may also develop dengue shock syndrome, a condition where severe bleeding leads to a rapid drop in blood pressure and causes the body to go into shock.
The above map shows all countries for which the CDC has issued a level 1 travel advisory due to the spread of dengue fever
Children under five, adults over 65 and pregnant women are considered to be most at risk from the virus.
Dengue was virtually eradicated from the US in the 1970s, but sporadic outbreaks have been recorded since, particularly in warmer states, including Florida and California. Most cases recorded in the US are linked to international travel.
There is no specific cure for dengue fever and treatment consists of supportive care and therapies to manage symptoms and complications.
Doctors recommend patients with mild symptoms drink plenty of fluids and take Tylenol to ease pain.
In severe cases, patients may be admitted to the hospital for supportive care, an IV, blood pressure monitoring and a transfusion to replace lost blood.
To protect against dengue fever, there is a three-dose vaccine available, which is recommended for children aged nine to 16 years. It slashes the risk of a symptomatic infection by about 80 percent.
