A few months ago, the Centers for Disease Control and Prevention published a startling map that showed the parts of the U.S. that could harbor mosquitoes capable of carrying Zika.
Many readers, including myself, thought, “Zika could come to my town! It could come to Connecticut! To Ohio and Indiana! Or to northern California! Oh goodness!”
The map made it look like a vast swath of the country was at risk for Zika, including New England and the Upper Midwest.
Well, not quite.
On Thursday, CDC scientists published another mosquito map for the U.S. And it paints a very different picture.
The new map shows counties in which scientists, over the past two decades, have collected Aedes aegypti mosquitoes — the type of insect thought to be spreading Zika in Latin American and the Caribbean.
“The new map is more accurate than the initial one,” says Thomas Scott, an entomologist at the University of California, Davis. “The distribution of the A. aegypti mosquito is much more restricted than the initial map showed.”
In the map, counties colored yellow reported A. aegypti mosquitoes during one year between 1995 to 2016. Orange counties had the mosquitoes in two years. And red counties are the hotspots: Scientists there found A. aegypti mosquitoes during three or more years in the past two decades.
This map represents “the best knowledge of the current distribution of this mosquito based on collection records,” entomologist John-Paul Mutebi and his colleagues at the CDC wrote in the Journal of Medical Entomology.
Many of the hot spots for this mosquito aren’t surprising. They’re places that we already knew are vulnerable to Zika, including counties in southern Florida, along the Gulf Coast and southern Texas. These places have had problems with a virus closely related to Zika, called dengue. They’re already on high alert for Zika.
But several hot spots are bit more unexpected — and concerning. “Perhaps the most concerning development for A. aegypti is its establishment in the Southwest, most recently in California in 2013,” Mutebi and his co-authors write.
Other surprises include parts of the Bay Area, greater Washington, D.C., and the Dallas-Fort Worth region, which all have established populations of A. aegypti, the map shows.
Continue reading at NPR.
Image credit: Centers for Disease Control and Prevention