Florida's Dengue Outbreak Kills Tampa Woman, 80, in Largest U.S. Mainland Surge in Decades

On the last Friday of August, Gay Rabb Small took her daily walk along the Tampa shore — at least five miles, as she did every day, determined to stay healthy as she neared 80. That night at dinner, her daughter Anna noticed she seemed off. By Saturday she had developed a tremor. By the following Friday, September 4 — her 80th birthday — she was dead.

Gay Small had dengue. She almost certainly caught it from a mosquito bite on one of those walks. Her death certificate listed dengue infection, septic shock, and multi-organ failure, according to the Tampa Bay Times. She is the only confirmed fatality so far in a Florida outbreak that public health officials and researchers are calling the largest locally acquired dengue outbreak in the continental United States in nearly a century.

I thought she had overdone it.— Anna Small, daughter of Gay Small

Florida's Department of Health recorded 524 locally acquired cases as of the week ending October 31, according to The Florida Press — more than double the previous state record of 199 cases set in 2023, and more than eight times the 62 cases recorded all of last year. The outbreak is concentrated in the Tampa Bay area: Hillsborough County, which encompasses Tampa, accounts for 407 of those cases, with Pinellas County adding 80 more.

There is a cautious sign that the worst may be passing. Hillsborough added just 22 new cases in the week of October 25–31, its smallest weekly increase since mid-August and well below its peak of 53 cases in a single week in late September, according to The Florida Press. The state recorded 39 new local cases that week, down from 60 the week before. But County Administrator Bonnie Wise extended Hillsborough's local emergency through November 12, and mosquito surveillance is still detecting the virus in local mosquito populations, including in a populated area northeast of downtown Tampa.

I have not seen anything like this.— Eva Buckner, insect scientist, University of Florida

What makes this outbreak particularly alarming to public health experts is not just its size but its source: most transmission is local, not imported. In the continental United States, dengue cases have historically been almost entirely traceable to mosquito bites acquired while traveling abroad. Local transmission — where a mosquito bites an infected traveler and then passes the virus to someone who never left home — has been rare.

It is very unusual to have transmission in the United States. This is so very much of an eye-opener.— Eva Harris, professor of infectious diseases and vaccinology, University of California, Berkeley

Scientists told WUSF, as reported by The Florida Press, that the weather set the stage: a long drought allowed drought-resistant Aedes aegypti mosquito eggs to accumulate in the environment, then June rains hatched them all at once, just before a hot, humid summer. Infected travelers returning from places where dengue is endemic — Cuba was the country of exposure for 323 of Florida's 382 travel-associated cases this year — brought the virus in, and local mosquitoes spread it. Nearly all locally acquired cases typed so far are the DENV-2 serotype; 20 mosquito pools have tested positive for DENV-2, 19 of them in Hillsborough County.

That is the $100 million question. Maybe it is associated with higher introductions through travelers to the Caribbean. But we're still trying to work out why we're seeing more cases this year.— Dr. Gabriela Paz-Bailey, chief of the dengue branch, CDC division of vector-borne diseases

The outbreak has triggered emergency declarations in Hillsborough, Pinellas, and Pasco counties, and $800,000 in emergency CDC funds for mosquito surveillance and control. Hillsborough has been running nighttime helicopter applications of Dibrom adulticide and daytime flights applying a bacterial larvicide called Bti — which health officials say is not harmful to people, pets, or pollinators — over affected neighborhoods. On October 10, Governor Ron DeSantis issued an executive order adding mosquito control to an existing order responding to Hurricane Isaias flooding.

The outbreak has also spread geographically. Locally acquired cases have now been confirmed in 12 Florida counties. A new positive mosquito pool — Aedes aegypti mosquitoes testing positive for DENV-2 — was reported in Citrus County as recently as October 27, according to The Florida Press. In South Florida, heavy rains that flooded parts of Broward County are raising fresh concerns: Davie has begun mosquito spraying, and officials are assessing whether additional aerial treatment is needed.

The longer-term picture is sobering. Researchers estimate that roughly 18% of the global dengue burden between 1995 and 2014 was attributable to climate change, based on a study of 21 countries in Latin America and Asia, according to The Florida Press. Projections cited by WUSF show dengue transmission rising 49% by 2050 under a best-case emissions scenario and 76% under a worst-case scenario.

We project a pretty large further increase in dengue transmission by mid-century.— Erin Mordecai, Stanford University

I think the dengue outbreaks will get worse over the coming years in the U.S.— Ira Longini, biostatistician, University of Florida

Dr. Paz-Bailey said she does not expect 'explosive' outbreaks like those in Puerto Rico, given the higher standard of living in the continental U.S. But she added: 'I do think that we will continue to see locally acquired dengue — that this will become the norm.' There is currently no dengue vaccine approved in the United States, and available vaccines are not highly effective, according to experts. Treatment remains supportive — managing pain and fluids.

The outbreak is unfolding as Florida voters approved a property tax cut that critics say will cost local governments billions in revenue and could reduce public services, including mosquito control, according to dnyuz.com. Infection rates are expected to decline as weather cools, since mosquitoes breed less effectively and are less infectious in cooler temperatures.

Why it matters — Florida's 2026 dengue outbreak marks a potential turning point in which locally acquired dengue — once nearly absent from the continental U.S. — becomes a recurring public health threat, with experts warning that climate change and travel patterns will make future outbreaks larger.

Reported by watchers.news, dnyuz.com, thefloridapress.com