[credit provider=”Wikimedia/CDC” url=”http://en.wikipedia.org/wiki/File:Aedes_Albopictus.jpg”]
The viral infection dengue fever is usually associated with tropical areas, but the disease has been spreading, even into the tropical areas of the United States: Texas, Florida and Hawaii.Dengue is common in other areas, infecting 100 million people a year. 500,000 of them end up hospitalized, and about half of those die. There are also huge costs to the labour force, because the infection can last for months. It is spread by mosquitoes.
At the annual meeting of the American Society of Tropical Medicine and Hygiene last month, researchers from the University of Florida revealed that dengue has reappeared in Key West, Fla. The virus they found was not a one-time visitor imported by a tourist or a stray mosquito; it has been on the island long enough to become a genetically distinct, local strain.
The Florida researchers didn’t want to talk about their presentation because they hope to get it published soon in a medical journal. But it turns out other tropical-disease experts have been watching dengue’s return to the United States for a while and wondering what it will mean.
“It really is just a matter of time until dengue re-establishes itself in certain areas here,” says Amesh Adalja of the centre for Biosecurity of the University of Pittsburgh Medical centre. “The U.S. has been lucky that it has escaped so far.”
122 people were infected with dengue in Hawaii in 2001, the first time that the disease has been seen there since 1944. A separate outbreak in Brownsville, Texas, in 2005 infected 25, and 90 cases were reported in Key West between 2009 and 2010.
“It may not swamp the entire U.S.,” Adalja told McKenna. “But the entire South already harbors those mosquitoes, and that is bad enough. Dengue shouldn’t have to swamp the entire country for us to make it a priority.”