Dengue Fever in Florida: What Actually Protects You?
A daytime repellent on exposed skin, screens that actually close, and no standing water around the house. That is what stops Florida's dengue outbreak at your door, and it matters now because the state is in the middle of the largest continental US dengue outbreak since the 1940s with no vaccine available to residents. Most infections stay mild. But if you're over 60, pregnant, diabetic, hypertensive, or you've had dengue before, the odds of severe disease climb sharply.
Florida has had locally acquired dengue before. 2026 is different. State surveillance has confirmed 252 locally acquired cases, 223 of them in Hillsborough County around Tampa Bay, along with one death in an 80-year-old resident. The previous recent high was 199 cases in all of 2023, and only 85 the year after. What hasn't changed is what protects you: there's still no dengue vaccine for people living in the continental US, so the whole task is keeping Aedes aegypti from biting you.
Why 2026 is the biggest year since the 1940s
Local dengue was essentially gone from the mainland US after the 1940s and only started trickling back in 2009, usually a few dozen cases a year in Florida or Texas. The jump this year isn't a mystery. Global dengue hit a record 14.1 million cases in 2024, mostly in Latin America and the Caribbean, and Florida sits downstream of that. The state has also logged 245 travel-associated cases in 2026. Each one is a seed waiting for a local Aedes aegypti to bite an infected traveler and then bite a neighbor. Hillsborough County has extended a local state of emergency into October and ramped up aerial and ground spraying after finding dengue virus in trapped mosquitoes.
Who actually gets seriously sick
Most dengue infections are quiet. Roughly half of people who get infected have no symptoms, and overall case fatality stays well under 1% when care is available. The people who do badly aren't random. Severe-disease risk roughly triples in adults with diabetes and in pregnant women, and roughly doubles in adults over 60 and in people with hypertension. A second lifetime infection with a different serotype pushes severe-disease risk up two- to threefold, because antibodies from the first infection can paradoxically make the next one worse. Children well above a healthy weight also run higher odds of hospitalization.
If you fit one of these descriptions and you develop a sudden fever with headache, body aches, or pain behind the eyes in the next few weeks, treat that as a reason to get tested rather than wait it out.
What actually keeps Aedes aegypti from biting you
Aedes aegypti bites during the day, lives in and around houses, and breeds in anything that holds water for a few days: a plant saucer, a bucket, a bottle cap, a clogged gutter. Controlled trials and household studies converge on a short list of measures that work, and a shorter list that doesn't.
| Measure | What the evidence shows | Takeaway |
|---|---|---|
| DEET 20% to 30% | Multi-hour bite protection against Aedes aegypti in controlled testing | The workhorse; reapply every few hours during the day |
| Picaridin 20% | Comparable multi-hour protection, with less skin irritation | An equally good choice if you dislike DEET |
| Window and door screens | Roughly 80% lower odds of dengue in household studies | The best fixed-cost measure in your home; install or repair any gaps |
| Dumping standing water weekly | Reduces vector production and household transmission in community trials | Walk the yard; empty saucers, buckets, toys, bottle caps; clear gutters |
| Spatial (plug-in) repellents | Cut arboviral seroconversion by about a third in a cluster-randomized trial | A reasonable add-on indoors, not a substitute for repellent or screens |
| Insecticide-treated curtains or coils alone | No reduction in dengue in trials; coils linked to higher infection odds in some studies | Don't rely on these as your main defense |
| Dengue vaccine (Dengvaxia or Qdenga) | Dengvaxia is being discontinued and was never indicated for Florida residents; Qdenga isn't approved in the US | Not an option for continental US residents in 2026 |
The vaccine gap, and why it matters now
Two dengue vaccines exist, and neither will help you in Florida this year. Sanofi's Dengvaxia is the only one FDA-approved in the US, but it was never meant for Florida: the official recommendation covers only children ages 9 to 16 who live in endemic US areas (Puerto Rico, the US Virgin Islands, American Samoa, and the Pacific territories) and have a lab-confirmed prior dengue infection. Sanofi is discontinuing it, with the last doses expiring around August 2026.
Takeda's Qdenga, approved in roughly 40 countries, isn't available here. Takeda withdrew its FDA application in 2023 after regulators asked for more data, and nothing has replaced it. In the pivotal phase 3 trial, Qdenga protected people who had already had dengue durably; in dengue-naive recipients it covered serotypes 1 and 2 but showed no efficacy against serotype 3, which is part of why its US path has stalled.
Informed, not alarmed
If you live in Florida and you're not in a high-risk group, use a daytime repellent outside, close the screens that close, and keep standing water off your property. That's it. If you're over 60, pregnant, diabetic, hypertensive, obese, or you've had dengue before, do the same things seriously, and treat an unexplained fever in the next few weeks as a reason to get a dengue test early rather than ride it out.
Three things would change this answer: FDA approval or expanded access for Qdenga, a CDC advisory specific to the Florida outbreak, or confirmation that a second dengue serotype has settled into Tampa Bay.