Health workers responding to an Ebola outbreak in Guinea had no maps to go on, so they turned to the internet for help

Information helps (Image: Youssouf Bah/AP/Press Association Images)

WHEN doctors working for Médecins Sans Frontières (MSF) arrived in the West African nation of Guinea last month to combat an outbreak of the deadly Ebola haemorrhagic fever, they found themselves working in an information vacuum.

Accurate maps are crucial to pinpointing the source of the Ebola virus and preventing it from spreading. But the only maps in Guinea were topographic charts – useless for understanding population distribution. Desperate for information, they enlisted an online army to help.

MSF asked a digital mapping organisation called Humanitarian OpenStreetMap Team (HOT) to build them a map of Guéckédou, a city of around 250,000 people in southern Guinea, where the outbreak is concentrated.


As of 31 March, online maps of Guéckédou were virtually non-existent, says Sylvie de Laborderie of cartONG, a mapping NGO that is working with MSF to coordinate the effort with HOT. “The map showed two roads maybe – nothing, nothing.”

Within 12 hours of contacting the online group, Guéckédou’s digital maps had exploded into life. Nearly 200 volunteers from around the world added 100,000 buildings based on satellite imagery of the area, including other nearby population centres. “It was amazing, incredible. I have no words to describe it. In less than 20 hours they mapped three cities,” says de Laborderie.

Mathieu Soupart, who leads technical support for MSF operations, says his organisation started using the maps right away to pinpoint where infected people were coming from and work out how the virus, which had killed 95 people in Guinea when New Scientist went to press, is spreading. “Having very detailed maps with most of the buildings is very important, especially when working door to door, house by house,” he says. The maps also let MSF chase down rumours of infection in surrounding hamlets, allowing them to find their way through unfamiliar terrain.

Soupart says that without the new maps the organisation would have had to rely on old army maps, Google Earth and hand-drawn maps. “We would have asked the government and local authorities if they have some maps, but in this case we know the answer would have been negative,” he says. Instead, MSF now has up-to-date maps of the whole area. Workers are each given an A4 printout of a specific area to canvass door to door, surveying inhabitants and searching for signs of the disease. The pages can then be assembled into a larger map to provide the big picture.

Mikel Maron, co-founder of HOT, says the group’s work with the American Red Cross in response to typhoon Haiyan showed aid organisations the potential for digital mapping. De Laboradorie agrees. “After the typhoon in the Philippines we got very, very interested by GIS [software] and maps in order to support their operation,” she says.

“The places that are among the most vulnerable to contagious disease outbreaks are also the least mapped,” says Maron. “We have real potential to help decrease that vulnerability.”

The places that are the most vulnerable to disease outbreaks are also the least mapped

HOT is also helping fight cholera in the Democratic Republic of the Congo, where it has been enlisted by MSF’s UK arm to build detailed street maps of Lubumbashi, the country’s second largest city. There, the location of each cholera case is tagged on a map, helping to trace outbreaks of the disease back to their source, which is usually contaminated water.

Information on each Ebola case is also being added to the maps built by HOT. While the new maps are available for anyone to use online via OpenStreetMaps, the case information won’t be uploaded to the public OSM map of the city, due to its sensitive nature. But it will help MSF efforts to identify the outbreak’s patient zero – and hence where the Ebola outbreak originated.

The global nature of the mapping effort is stunning, says de Laborderie. “When you are going to sleep at the end of the day, another part of the world is mapping.”

This article appeared in print under the headline “Mapping in a crisis”