Dengue fever, a debilitating mosquito-borne illness often called 'breakbone fever,' is showing a growing presence in the United States, with recent outbreaks and potential fatalities raising public health concerns. In Florida's Hillsborough County, health officials issued a mosquito-borne illness alert in August following reports of multiple locally acquired dengue cases. This cluster includes the family of a Florida woman who claimed doctors attributed her death to the virus, underscoring the severe potential of the disease.
Dengue fever is transmitted through the bite of infected Aedes mosquitoes, primarily Aedes aegypti, a species common in warm, urban environments, including parts of Florida. These mosquitoes can breed in small amounts of standing water and are active during daylight hours. The disease cycle involves a mosquito biting an infected person and then transmitting the virus to others. A significant challenge is that roughly 75% of dengue infections cause no symptoms, making it difficult to track and control. For those who do develop symptoms, they typically appear four to 10 days after the mosquito bite and can include sudden high fever, severe headache, pain behind the eyes, muscle and joint pain, nausea, vomiting, and rash.
Severe Dengue and Its Risks
While most dengue infections resolve within a week, about one in 20 patients can develop severe dengue, a life-threatening condition that often emerges as the fever subsides. Symptoms of severe dengue include intense abdominal pain, persistent vomiting, bleeding from the gums or nose, extreme drowsiness or restlessness, and blood in vomit or stool. Individuals with underlying health conditions such as diabetes, obesity, or kidney disease, as well as infants, pregnant women, and adults over 65, are at higher risk of progressing to severe illness. Without prompt medical care, severe dengue can be fatal in up to 10% of cases, though hospital treatment reduces this mortality rate significantly.
Global Surge and US Exposure
Dengue fever is surging globally, with the World Health Organization recording over 14 million cases in 2024 across approximately 100 countries, a substantial increase from previous years. Factors such as warmer temperatures, rapid urbanization, and international travel are contributing to the virus's expansion into new regions. While South Asia, Southeast Asia, and Latin America bear the brunt of the disease, its reach is extending northward.
In the United States, most dengue cases are still reported in travelers returning from endemic areas, with nearly 1,900 such cases reported by the CDC in 2023. However, locally acquired cases are becoming more frequent in states with suitable climates for Aedes mosquitoes. Florida leads among the contiguous states, with Miami-Dade County alone recording over 300 locally acquired dengue infections between 2010 and 2024. Cases have also been documented in Texas, California, Arizona, and Hawaii. US territories like Puerto Rico and the U.S. Virgin Islands experience a higher burden of the disease.
Prevention and Treatment
There is no specific antiviral treatment for dengue fever. Medical care focuses on supportive measures, including rest, ample fluid intake, and acetaminophen for fever and pain. Patients are advised to avoid aspirin, ibuprofen, and other non-steroidal anti-inflammatory drugs, as these can increase the risk of bleeding. Severe cases require hospitalization for careful management of fluid balance and close monitoring to prevent complications like shock or organ damage.
Preventative measures include using insect repellent, wearing protective clothing that covers arms and legs, and eliminating standing water around homes and communities where mosquitoes can breed. Health officials urge individuals experiencing sudden fever after traveling to dengue-prone areas or after potential mosquito exposure in affected regions to seek medical attention promptly and inform their doctors about their travel history or potential exposures. Recognizing the warning signs of severe dengue and seeking emergency care immediately is critical for improving patient outcomes.