Florida health officials confirmed on Friday that locally acquired dengue fever, a mosquito-borne viral illness, was the case of death of Tampa woman this month.
The Department of Health’s announcement did not provide additional details, although the Tampa Bay Times previously reported that the 80-year-old was bitten by a mosquito near her home on Bayshore Boulevard. She died Sept. 4.
The woman was among at least 134 patients with locally acquired dengue this summer in Hillsborough County, about 90% of the cases statewide.
“This is wildly unusual for us,” said Chris Wilkerson, a spokesperson for the county.
Hillsborough had experienced only sporadic cases until this year — two between 2015 and 2025, according to health department records and mosquito control officials.
However, recent samplings of mosquito pools have not been finding the virus, a sign that the likelihood of new infections is waning, said Paolo Pecora, senior environmental scientist for Hillsborough County Mosquito Management Services.
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The virus is spread by Aedes aegypti and Aedes albopictus, warm-weather mosquito species common in Florida, according to the Centers for Disease Control and Prevention. The outbreak is likely tied to recent weather that allowed them to multiply.
“We are seeing warmer temperatures and lots of rain. This gives these mosquitoes plenty of places to breed,” Kristy Miley, an infectious disease researcher with the USF College of Public Health, said in a university article.
Dengue is typically transmitted when a mosquito bites an infected person and then passes the virus to another person through a subsequent bite.
These mosquitos stay in the neighborhood
Health officials say Aedes mosquitoes typically stay where they hatch, rarely traveling more than a few hundred feet. They “live very close to people in and around homes,” Miley said.
As a result, control efforts focus on identifying and treating areas near confirmed cases. Eliminating larvae and breeding sites can reduce numbers available to carry the virus.
Hillsborough mosquito control workers have been stepping up aerial and ground pesticide spraying with help from Pasco County, part of an agreement to supplement mosquito-control operations.
Crews also have been checking properties for standing water, including in tires, where mosquitoes might breed, Pecora said.
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Health officials reiterated that even with aggressive pesticide spraying, prevention efforts by residents can be more effective in limiting mosquito populations.
They are asking people to drain water from discarded tires, buckets, pool covers, coolers, toys, flowerpots, plant leaves or anywhere else it may collect from sprinklers or rain.
They also recommend that people:
• Use a federally registered insect repellent with these active ingredients: DEET, picaridin, IR3535, oil of lemon eucalyptus, para-menthane-diol or 2-undecanone.
• Wear loose-fitting, long-sleeved shirts and long pants while outside and avoid areas with high mosquito populations, especially at sunrise and sunset.
Outbreaks can start when a person travels, gets infected and then is bitten back in the U.S. by a mosquito capable of spreading the virus. It can mushroom from there, said Michael von Fricken, a University of Florida associate professor of environmental and global health.
Given the recurring abundance of those kinds of mosquitoes in Florida, the threat of dengue is not likely to tail off, he added. “I do think it’s going to be somewhat the new normal,” he said.
Dengue deaths are rare in the U.S.
Dengue rarely results in death in the U.S., where it typically is found in people infected while visiting areas of the world with higher risk, such as Puerto Rico, and South American and Caribbean countries.
According to Miley, the Tampa woman’s death marks the first tied to dengue in the Tampa Bay area in nearly a century.
Dengue presents as flu-like symptoms, including severe muscle aches, headaches. joint pain, fever and occasional rashes. Symptoms usually start within 15 days of a mosquito bite. Hospitalizations are common for severe cases, which may cause bleeding or shock.
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Many infected people don’t get sick, meaning the number of cases reported in an outbreak can be an undercount of the real number of infections.
The state's largest outbreak, with nearly 200 cases, was in 2023. This year’s total already ranks second, with Hillsborough considered an “epicenter,” according to Surgeon General Dr. Joseph Ladapo.
The last major dengue outbreak in Florida occurred in Monroe County in 2020, with 72 locally acquired cases, while earlier outbreaks occurred in Key West in 2009-10 and Martin County in 2013.
Across the world, more than 2.2 million infections have been reported so far this year, according to the World Health Organization, and nearly 1,200 people have died.
In the United States, there have been nearly 1,500 locally acquired U.S. cases, most of them in Puerto Rico, according to the CDC.
Pinellas County added two locally acquired dengue cases in the health department's most recent reporting period and has seven since July. Four other counties have reported dengue this year — including Miami-Dade, which also has had seven cases.
Meantime, two more locally acquired dengue patients were reported Friday in the Apopka area of Orange County, prompting health officials there to issue a mosquito-borne illness alert. Another case was reported in Orange County earlier this month.
As of Aug. 29, there were mosquito-borne illness advisories in Alachua, Brevard, Leon, Palm Beach, Pasco, and Walton counties. Mosquito-borne illness alerts are in Hillsborough, Pinellas, Duval, Orange and Miami-Dade.
Information from the Associated Press was used in this report.
