Zika Virus Risk Calculated for 50 US Cities

Southern regions of Texas and Florida are likely to experience the largest outbreaks of mosquito-borne Zika virus this spring and summer, according to a new projection of the infectious disease’s impacts on 50 U.S. cities.

Weather, travel, and poverty will be key drivers of Zika’s spread in certain regions of the U.S., according to the National Center for Atmospheric Research report.

The Aedes aegypti mosquito, which is spreading the virus in Latin America and the Caribbean, will likely be common in the southern and eastern United States as the weather warms, according to insect and disease experts at the NCAR.

Conditions are also expected to be favorable for mosquito populations to pose a threat along the East Coast as far north as New York City and across the southern tier of the country as far west as Phoenix and Los Angeles, according to specialized computer simulations conceived and run by researchers at NCAR and the NASA Marshall Space Flight Center.

"This research can help us anticipate the timing and location of possible Zika virus outbreaks in certain U.S. cities," said NCAR scientist Andrew Monaghan, the lead author of the study. "While there is much we still don't know about the dynamics of Zika virus transmission, understanding where the Aedes aegypti mosquito can survive in the U.S. and how its abundance fluctuates seasonally may help guide mosquito control efforts and public health preparedness."

The researchers noted that long-range forecasts for this summer point to a 40-45 percent chance of warmer-than-average temperatures for most of the United States.

But Zika is unlikely to spread across the U.S. as widely as in Latin America and the Caribbean, in part because Americans live and work in air-conditioned and largely sealed homes and offices, the researchers said.

The study, published today in Public Library of Science journal PLOS Currents Outbreak, was funded by the National Institutes of Health, NASA, and the National Science Foundation (NSF). It included scientists at the NASA Marshall Space Flight Center, North Carolina State University, Maricopa County Environmental Services Vector Control Division, University of Arizona, and Durham University.

For a map of cities with greatest risks, click here.