Dengue is a human disease caused by any of four closely related viruses (dengue-1, -2, -3, -4). Dengue historically plagued Florida until 1934, which was the last epidemic year within the state until 2009. Since 1934, imported cases have been documented yearly in Florida. These are cases where Florida residents were infected by mosquito bites while visiting other countries with active virus transmission, but they did not become ill until returning to Florida. The Florida Keys experienced an outbreak of dengue in 2009 and 2010, followed by a small focal outbreak in Martin County in 2013. Only one locally acquired dengue case transmitted by Florida mosquitoes was reported during 2015, while 86 Florida residents received dengue infections while traveling out of country. As of June 2016 one locally acquired dengue case was reported in Florida, a tourist infected with dengue during a visit to Key West.