Florida Dengue Outbreak Becomes Largest in Continental U.S. in Decades

Florida is experiencing its largest dengue outbreak in decades, with 252 locally acquired cases reported as of late September — among the highest totals the continental United States has seen since at least the 1940s.

The vast majority of cases have been reported in Hillsborough County, home to Tampa, where officials are ramping up mosquito-control efforts. The surge has prompted Hillsborough, Pasco and Pinellas counties to declare local states of emergency, stepping up efforts to eliminate standing water where Aedes aegypti and Aedes albopictus mosquitoes breed.

Florida's locally acquired case total has already surpassed the state's previous annual high of just under 200 cases, reported in 2023. The current outbreak is nearing the 264 locally acquired cases reported in Hawaii over six months in 2015 and 2016 — the largest U.S. state outbreak in decades, though federal health officials caution that national dengue surveillance data is limited.

Dengue is a viral infection spread primarily through mosquito bites. Most people recover, but severe cases can cause bleeding, shock and death. Florida has reported one dengue-related death this year: an elderly Tampa woman who died on September 4.

Florida also recorded 245 travel-associated cases this year, with at least 13 Hillsborough County cases involving people who had recently traveled. Public health experts say it remains unclear why the outbreak has concentrated around Tampa rather than its historical epicenter in South Florida. Travel patterns, warmer temperatures, and climate conditions creating more favorable environments for mosquitoes may all be factors.

The CDC has provided Florida with $800,000 in emergency funding. The agency has not sent disease investigators because state officials have not requested them. Nationally, local transmission of dengue has occurred in Florida, Texas, Hawaii, Arizona, and California in recent years, though Florida's current case count is on another scale entirely.

The Florida outbreak comes as dengue circulates at high levels globally. More than 2.2 million infections and nearly 1,200 deaths have been reported worldwide this year, according to the World Health Organization — figures that are likely undercounts due to asymptomatic cases and under-testing.

Reporting by The Independent. Read the original report: This state's dengue outbreak is now the largest in the US in decades.