Public health officials in Key West, Florida, are now battling dengue fever, a tropical disease believed to have been eradicated from the United States over 70 years ago.
Until 2009, Florida had not seen a locally contracted case of dengue fever since 1934. There were 27 confirmed cases of dengue in Key West it 2009. Last year, the number rose to 66 people, according to NPR.
"Typical dengue fever is a severe, flu-like illness," Mark Whiteside, medical director at the Monroe County Health Department in Key West, said, NPR reports. "It might last a week or two. You might wish you were dead, but almost everybody gets over it."
Dengue fever is rapidly becoming a serious public health threat in Key West, Hawaii, south Texas and several other Florida counties. Growth in international trade and travel has aided in bringing the illness back to the United States, but it is the Aedes aegypti mosquito, the dengue vector, that is the most crucial factor in disease’s resurgence.
"The carrier of dengue, the vector of dengue — the Aedes aegypti — is more widespread and abundant than ever before in history. That's obviously part of the reason we have dengue back," Whiteside said, according to NPR.
The Key West Mosquito Control District has made managing the Aedes aegypti population a top priority, but it is a complex task. The health department has joined the Mosquito Control District in advising residents and businesses about mosquito control.
"A lot of places here in Key West, they don't have screens," Andrea Leal, an entomologist and deputy director of the Mosquito Control District, said, NPR reports. "They leave doors wide open. So this particular mosquito, they can breed outside, in let's say a water-holding bucket. And then once the adults come off, they'll move inside the home and feed on people inside the home."
There have been no reported cases of dengue so far this year in Key West, but the rainy season, the mosquitoes’ peak, has just begun.
Duane Gubler, a dengue expert and the director of Duke University’s Program in Emerging Infectious Diseases in Singapore, said that the threat from the Aedes aegypti involves more than just dengue fever. The mosquito is also a carrier of other tropical diseases that are beginning to reemerge, including yellow fever.
"If we start seeing urban transmission of yellow fever in tropical America, it's going to move very quickly to the United States and to the Asia-Pacific region," Gubler said, according to NPR. "And it will create a global public health emergency if that happens. So, I think the risk of yellow fever is very real."