The Value of Mapping the Ebola Outbreak

In June 2020, during the COVID-19 pandemic, new Ebola Virus Disease (EVD) cases were confirmed in western Democratic Republic of the Congo (DRC). Unrelated to the Ebola outbreak winding down in the eastern part of the country, these cases marked the beginning of DRC’s 11th Ebola outbreak, and its third one in three years, with a previous outbreak occurring in the same region just two years prior.

The CDC’s Emergency Operations Center Situational Awareness team relied on geospatial expertise from CDC/ATSDR’s Geospatial Research, Analysis, and Services Program (GRASP) program, whose maps, analysis, and data coordination gave officials critical insight into which areas to focus on for the response.

The first EVD cases were found near the busy river port city of Mbandaka, the capital city of Équateur Province located on the Congo River. This river is an important transportation hub, connecting millions of people to villages and cities throughout the region.

As more EVD cases increased in multiple locations throughout Équateur Province, finding reliable data of settlements or where people lived was a challenge.  

Updating Existing Maps and Data

To get a clear and accurate picture of Équateur Province, an area slightly larger than the US State of Virginia, GRASP GIS Analyst Jeff Higgins (contractor, Perspecta), analyzed existing maps and data. Unfortunately, in many cases, existing Geographical Information System (GIS) data for Équateur Province boundaries, which are divided into geographic areas, were outdated or non-existent.

To create more accurate maps of areas with EVD cases, Higgins initiated a comprehensive, multi-step process to

  • view satellite images
  • review hand-drawn maps
  • match existing borders with landmarks, such as buildings and rivers
  • determine the boundaries that belong with the appropriate villages
  • update names of areas that were listed differently in multiple sources
  • decide what data gaps exist based on various sources

Higgins’ newly created maps served as a useful resource offering officials a more granular level of detail. The maps showed healthcare facilities throughout the region, highlighted initially affected areas  and their distance from the eastern DRC outbreak, and provided incident management and leadership increased awareness.

Geospatial Approaches Provide Quality Data

GRASP’s long history of supporting CDC’s Emergency Operations Center began in 2003. Higgins’ previous geospatial support and knowledge during the 2018 Ebola outbreak in eastern DRC provided a foundation for his support to the Ebola outbreak response in the western part of the country in 2020.

“People don’t always appreciate the long journey of creating maps and how valuable they are for responding to emergencies—from interpreting data on PowerPoint slides to gain insights on where to send responders on the ground, to showing leadership exactly where the outbreak is occurring and how close clusters are,” says CDC Division of Global Health Protection Health Scientist Dante Bugli.

Throughout the response, other GRASP team members assisted with cartographic requests (map-making) for print and presentations, ad hoc boundary maps, and data coordination, including GIS Analyst Nina Dutton (contractor Perspecta), GIS Analyst David Rickless (contractor Perspecta), and GIS Analyst Lance Owen, ORISE Fellow. With these map products, authorities responding to the outbreak had a better understanding of the area.

Specifically, the mapping products and data coordination activities were useful for

  • CDC public health professionals working in the Emergency Operations Center, who shared maps with the Secretary of the Department for Health and Human Services (HHS) early in the response
  • CDC’s Office of Safety, Security, and Asset Management, who provided logistics and security personnel and helped identify where to  place a remote lab
  • US government officials, who used the maps to stay up to date about the outbreak
  • Healthcare workers in the field, who used the maps for situational awareness
  • Partners in the neighboring country of Republic of the Congo, who requested maps of affected areas in western DRC and updated maps of eastern DRC, for inclusion on their public-facing website 

Near the end of the outbreak, there was concern that the virus may have spread across the river from DRC to the Republic of the Congo. Health officials requested maps showing populations living along the river border between the two countries. With these maps, officials could measure distance and visualize locations with greater detail. Additional maps showed a more expansive view of the Congo River and other area rivers. CDC’s Emergency Operations Center used one of the border maps for situational awareness.

GRASP’s extensive analysis in creating accurate data and updated maps were critical in helping officials identify where people lived, where EVD cases were occurring, and where to send healthcare workers. On November 18, 2020, the Ebola outbreak in Équateur Province was declared over.

Since then, as an embedded team in CDC’s Emergency Operations Center, GRASP has continued to support domestic and international response efforts, including CDC’s response to COVID-19 and global polio eradication efforts.

Page last reviewed: November 17, 2021