Governments have used maps for everything from local economic development to snow plow tracking — now they’re also using it to fight the spread of the Zika virus.
Rather, U.S. government entities have been using the concept of geographic information systems (GIS) to help manage disease outbreaks and public health crises for a long time. But the open data movement and improved GIS platforms have helped make those maps a lot more useful.
Today, the Department of Health and Human Services’ Office of the Assistant Secretary for Preparedness and Response (ASPR) is using GIS to both track the spread of Zika in the U.S. and predict where it might cause the most damage in the future. The virus, carried by a couple species of mosquito, has raised fears as it comes to the U.S. after medical professionals linked it to birth defects in other countries.
Tracking the disease is a comparatively simple exercise — public health departments report cases of the virus, the Centers for Disease Control and Prevention gather them together.
But predicting where it might spread is a different beast entirely. Doing so means establishing where, based on things like temperature, elevation and habitats, the right kinds of mosquitos hatch and live. It means finding people who are likely to travel to countries with high incidence rates of the virus. Add in even more information — places where there are higher concentrations of sexually active women of child-bearing age who don’t have medical insurance, for example — and one can see, displayed neatly on a single map of the U.S. (at left), where Zika is poised to wreak the most havoc.
The uses are myriad at the federal, state and local levels, including public agencies' use of the map to prepare response plans, set up testing programs and target funding.
“[We use GIS] to make sure that we’re covering the potential area where Zika could spread and to make sure that the testing is happening in the same area,” said Rob Shankman, GIS lead for ASPR. “We don’t need to be testing in the Pacific Northwest yet … except for travel cases.”
Government can also use such information to simply find out where they can spend money the most efficiently. If officials can get out ahead of the disease, they can find people in its path and let them know how to best avoid getting it — using mosquito repellant and wearing long-sleeved shirts, for starters.
“We can communicate those kinds of things by targeting the right information to … people at risk,” said Este Geraghty, chief medical officer for GIS company Esri.
Alternatively, government can use the maps to help prevent spread of the disease via mosquito. David Totman, public works director for Esri, said local government can use mapped information to determine where to hit mosquitos before they hatch, and to improve prevention programs every single year.
“When the season’s over, you do analysis [of success]," he said, "and then you get ready for next year."
And with more and more data open to government, officials can be more sure of themselves when working with chemicals they use to kill mosquitos. Maps could help show where schools are, for example, or even where people are keeping bees that mosquito sprays could harm.
“The less chemicals that are used, the less impact on the environment,” Totman said. “[Public agencies are] always in this environmental stewardship balance.”
Without GIS, and dynamic maps in particular, making all the newly available data useful might be pretty difficult, Shankman said.
“So you would have knowledge of which counties have cases, but unless you can see which counties it’s next to … you wouldn’t be able to visually correlate how it’s moving across the country,” he said.
Even as recently as a decade ago, the utility of GIS in HHS was something of a different story. Most of what Shankman did back then was create static images of maps upon request. And though he still does that, he said he also makes products that are a lot more flexible.
“I’ve taken it from the static map where somebody asks for info and we send them a JPG or PDF of that map, and we’ve moved it all the way to online, dynamic, sharing of information, sharing of data to state and local government,” Shankman said. “We’ve moved it quite a ways now.”