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Dengue Fever: Facts, Figures and Prevention

The following, created with assistance from the Monroe County, Fla., Health Department, is provided to address any concerns or questions:

  • Dengue Fever is not a health threat in Key West. There have been no confirmed dengue fever cases in Key West since October 2010 and no health advisories were ever issued discouraging travel to Key West or the Florida Keys because of the virus.
  • Dengue is a viral disease only transmitted by the Aedes aegypti mosquito, a breed common to the southeastern United States and the tropics. It is not spread person to person.
  • Traditionally in the Keys and other Florida regions, mosquitoes are most active in summer and early fall and more dormant late fall through spring.
  • To help avoid being bitten by Aedes aegypti or other mosquito species, health officials advise using mosquito repellents that contain 20 percent to 30 percent DEET, picaridin or oil of lemon eucalyptus. DEET is not recommended for use on children younger than 2 months old. When inside, close windows and use air-conditioning. Or, if windows are open, check screens to ensure there are no holes.
  • Between overnight vacationers and cruise ship passengers, Key West hosts some 2.4 million visitors a year. Of 66 cases confirmed in 2010, nine were visitors, or .000003 percent of all tourists to Key West. All persons who acquired dengue in Key West fully recovered.
  • All confirmed cases were acquired in Key West and there is no evidence that infections spread elsewhere in the Florida Keys. The vast majority of dengue cases in Key West emanated from a .75-square-mile residential section in Old Town. No reported cases have originated outside of Key West.
  • The Florida Keys Mosquito Control District has an aggressive Aedes aegypti mosquito suppression and abatement program. New technologies used include aerial application of an innovative larvacide that targets the mosquito larvae and stops them from reaching adulthood. The larvacide is non-toxic to humans and animals.
  • More than 100 million cases of dengue occur every year worldwide, with year-round cases in the Caribbean and South and Central America. Symptoms of dengue can include high fever, headache, pain behind the eyes, backache, joint and muscle pains, nausea and vomiting, and sometimes rash. Care procedures normally involve seeking medical treatment for severe flu.
  • Many popular tropical visitor destinations, such as Puerto Rico and Brazil, are challenged with widespread dengue year-round.

More information is available via these links:

Or contact the Monroe County Health Department at 305-809-5653.