JONATHAN M. METSCH, Dr.P.H. – Tracking Emerging Public Health Challenges – October 20, 2026 – DENGUE
“As of October 10, 368 locally acquired dengue cases were reported in the state. Hillsborough County and the Tampa Bay area account for the bulk of the cases… (1)
“The virus dengue fever is spread from mosquito to human. And then, again, mosquito to humans,” Mulla said. “So, the mosquito is one that is responsible for transmitting the disease. You cannot get dengue by standing by somebody who has dengue.”
To fight back, Mulla says to check your yard at least once a week.
“We want you vigilantly to go around your house at least weekly. Check your rain gutters, make sure they’re flowing freely, because anything that has collecting water is going to be breeding mosquitoes,” she said.
That means dumping standing water in bird baths, buckets, toys, tarps and even kayaks.” (2)
“Dengue, Buckner also noted, is not endemic in Florida, meaning the state traditionally does not experience year-round transmission of the virus. Instead, there are isolated cases of local transmission or isolated outbreaks.
“Even though the virus is not endemic in our state, we have the mosquito, Aedes aegypti, and it is widespread in South Florida and Central Florida and a little bit into Northern Florida,” Buckner said. “Sometimes it can be found in the panhandle, but generally it’s too cold in the panhandle for it to survive overwintering, so you need multiple reintroductions there.”
How is Dengue Spread Locally in Florida? As an example of one way dengue spreads through local transmission in Florida, Buckner pointed to the consistent travel between Florida and Cuba, where the virus is endemic.
If someone visits Cuba, gets bitten by a mosquito infected with dengue, returns to Florida and another mosquito bites them, that mosquito becomes infected and can spread the virus. The same can be applied to other countries where dengue also is endemic.
“More people get sick and that leads to more mosquitoes getting infected by biting the infected people and so it can lead to a larger outbreak such as what we’re seeing in the Tampa Bay area,” Buckner said.” (3)
“One distinctive feature of dengue, however, is that the second time someone is infected is likely to be much worse than the first. Sometimes a second infection can progress to dengue hemorrhagic fever, which can involve bleeding and a drop in blood pressure, and is sometimes fatal.
This pattern, where the second exposure is more dangerous than the first, has complicated attempts to vaccinate people against the disease. In 2017, Sanofi Pasteur, the manufacturer of the dengue vaccine Dengvaxia, alerted the government of the Philippines that serious dengue infections might occur in people who had received the vaccine as their first exposure to the disease. No dengue vaccine is currently available in the U.S.; Dengvaxia was available starting in 2019 but in 2025 was discontinued by the manufacturer, which cited low demand.” (4)
As Florida Confronts Hundreds of Local Dengue Cases, Tampa Health Organizations Respond, By Noah Smith, https://www.directrelief.org/2026/10/florida-dengue-outbreak-tampa-hillsborough-cases/
St. Petersburg dengue patient, 73, shares experiences with the mosquito disease, https://www.wusf.org/health-news-florida/2026-10-19/st-petersburg-dengue-patient-73-shares-experiences-with-the-mosquito-disease
Citrus dengue cases rise to three, but no outbreak declared, https://www.chronicleonline.com/news/local/citrus-dengue-cases-rise-to-three-but-no-outbreak-declared/article_263996b4-c5da-5dc0-87dc-e1836ebfab39.html
A dengue vaccine is now available for travellers. Here’s what you need to know, https://theconversation.com/a-dengue-vaccine-is-now-available-for-travellers-heres-what-you-need-to-know-293803
“Dengue is an acute febrile disease caused by the Aedes mosquito-borne dengue viruses (DENV-1 to DENV-4). Annually, approximately 100 million people fall ill with dengue, which can cause debilitating pain and discomfort, reducing both physical functioning and quality of life. Some patients progress to life-threatening inflammation-driven circulatory failure. Disease burden remains primarily in urban centres; however, factors including increased travel and climate change are rapidly expanding the geographical distribution of dengue to rural and peri-urban environments. Dengue is diagnosed based on compatible clinical features, detection of viral RNA or antigens, or serological testing, depending on the phase of illness. There is no licensed antiviral or host-directed therapy for dengue; management is supportive, with close clinical monitoring and judicious fluid replacement to prevent circulatory failure while avoiding fluid overload. Thus, there is an increasing need for clinicians to be familiar with the clinical features, disease burden and management of dengue, along with the newly recognized post-acute sequelae. Although dengue vaccines have been licensed in several countries, their use has been restricted by uncertainties in dengue pathogenesis. Attention should be focused on how to use currently available vaccines to create the foundation of a larger strategy to mitigate dengue transmission and maximize public health impact.” (5)
1.Florida dengue: 2 locally acquired cases reported in Citrus County, by Robert Herriman, https://outbreaknewstoday.substack.com/p/florida-dengue-2-locally-acquired
2.Beach Mosquito Control District warns of West Nile advisory and Dengue, urges yard checks and repellent,By Alyssa Dutton, https://www.wjhg.com/2026/10/19/medical-monday-mosquito-illnesses-spreading-florida/
3.Florida Dengue Outbreak Reinforces Importance of Collaborative Control Efforts, by By McKenna Christy, https://www.pctonline.com/news/florida-dengue-outbreak-reinforces-collaborative-control-efforts/
4.What to Know About the Dengue Outbreak in the U.S., by Veronique Greenwood, https://time.com/article/2026/10/02/what-to-know-about-dengue-outbreak-florida-mosquito/
5.Dengue virus infection, by Yaw Shin Ooi, Jonathan Cattrall, Oliver Brady, Shirin Kalimuddin, Jue Tao Lim, Eduardo Lopez-Medina, Stephen J. Thomas, Sophie Yacoub & Eng Eong Ooi, https://www.nature.com/articles/s41572-026-00744-4
Curated by Jonathan M. Metsch, Dr.P.H.
Clinical Professor of Environmental Medicine, Icahn School of Medicine at Mount Sinai