Dengue fever, a mosquito-borne illness colloquially known as 'breakbone fever' for the severe joint and bone pain it causes, is increasingly being diagnosed in Florida. Dozens of people have contracted the virus locally in recent months, a significant shift from previous years where most U.S. cases were linked to international travel.
This year, 893 dengue cases have been reported across the United States. Of these, 40 were acquired within the U.S., with 39 occurring in Florida and one in Virginia. The Florida cases were concentrated in Citrus, Pinellas, and Hillsborough counties on the state's west coast.
The spread of dengue is facilitated by Aedes mosquitos, the same species that transmit Zika and yellow fever. These mosquitos thrive in warmer climates and are found in significant portions of the southeastern and southwestern United States. Researchers indicate that rising temperatures are expanding the habitable range for these mosquitos, with an estimated 75% of the U.S. now suitable for them.
This environmental shift has contributed to a notable increase in dengue cases. In 2024 alone, U.S. cases saw a 359% jump compared to the average over the past two decades. Infections have been documented in Florida, California, and Texas, suggesting multiple introductions of the virus rather than a single outbreak. A separate outbreak in New Jersey also affected dozens of people.
The Centers for Disease Control and Prevention (CDC) has noted that while these introductions haven't led to widespread U.S. outbreaks, they signal an escalating risk for locally acquired cases. The agency emphasizes the need for enhanced surveillance, vector control measures, and public health preparedness in areas populated by these mosquitos.
Dengue fever is a viral infection transmitted by the bite of an infected mosquito. While many infected individuals remain asymptomatic, others develop symptoms including fever, headache, nausea, rash, and severe body aches. In approximately 1 in 20 cases, dengue can progress to severe, life-threatening complications such as bleeding, a sudden drop in blood pressure, and organ failure. Without medical intervention, severe dengue can be fatal in up to 50% of cases.
There is no specific cure for dengue fever; treatment focuses on symptom management. This typically involves rest, staying hydrated, and using acetaminophen to alleviate fever and pain. Hospitalized patients may receive intravenous fluids to combat dehydration. The most effective prevention strategy is to avoid mosquito bites by using insect repellent, wearing protective clothing, and eliminating standing water around homes where mosquitos breed.
A dengue vaccine is available, but it is recommended only for individuals who have previously had the virus and reside in dengue-endemic areas. It is not advised for travelers or first-time infections, as it can potentially worsen the disease if contracted after vaccination.