Florida counties declare emergencies as dengue outbreak hits record levels

Florida is experiencing its largest locally acquired dengue outbreak in decades, with 252 local cases recorded by late September 2026, primarily in Hillsborough County. In response, Hillsborough, Pinellas, and Pasco counties declared local emergencies, granting crews the right to enter private property to eliminate mosquito breeding sites. The outbreak, dominated by the DENV-2 serotype, is linked to travel from Cuba and exacerbated by climate change, highlighting the lack of available vaccines in the United States.

Local emergency response measures

• ▪Hillsborough, Pinellas, and Pasco counties declared local states of emergency in late September 2026, invoking Florida's emergency-management law to combat the dengue outbreak.
• ▪The local emergency declarations in Florida authorize mosquito control crews to enter private property during daylight hours without notice to remove stagnant water.
• ▪Hillsborough County secured mutual-aid agreements with neighboring counties and Lee County's mosquito district to deploy helicopters for aerial larvicide and adulticide spraying.

Scale of the 2026 Florida outbreak

• ▪Hillsborough County, Florida is the epicenter of the state's 2026 dengue outbreak, accounting for 223 of the 252 locally acquired cases.
• ▪Florida recorded 252 locally acquired dengue cases as of late September 2026, marking the state's largest modern outbreak of the disease.
• ▪The Centers for Disease Control and Prevention reported 485 total dengue cases in Florida as of October 5, 2026, up from 392 cases on September 28, 2026.

First confirmed Florida death

• ▪Gay Small previously traveled to Asia and South America with her husband, whose work included efforts to fight infectious diseases.
• ▪An 80-year-old Tampa woman, Gay Small, died on September 4, 2026, marking Florida's first confirmed dengue-related death of the year.

Climate change and mosquito expansion

• ▪A 2022 United Nations Intergovernmental Panel on Climate Change report projected that expanding mosquito ranges could put an additional 2.25 billion people at risk for dengue globally.
• ▪Warm-weather Aedes mosquitoes are expanding their geographic reach in the United States due to climate change and rising global temperatures.

Dengue vaccine availability and challenges

• ▪There is currently no dengue vaccine available in the United States after Sanofi discontinued Dengvaxia in 2023 due to low global demand.
• ▪Brazil suspended its public vaccination campaign using the Butantan-DV vaccine in June 2026 while health officials investigate 42 adverse events, including two deaths.
• ▪Takeda Pharmaceutical voluntarily withdrew its U.S. Food and Drug Administration application for its Qdenga vaccine in 2023 following disagreements regarding data collection.

Debatable claims

• ▪Aerial insecticide spraying is an ineffective way to control dengue-carrying mosquitoes
• ▪The FDA's strict data requirements for dengue vaccines do more harm than good
• ▪Entering private property without notice to control mosquitoes is justified during public health emergencies