Key facts
- Health officials are using anonymized mobile-phone data to track Ebola spread in eastern Democratic Republic of Congo.
- This is the first time this approach has been used in an Ebola response.
- The outbreak, declared May 15, has infected over 6,250 people and killed 3,039.
- The virus is the Bundibugyo species of Ebola, with no approved vaccines or treatments.
- Swedish non-profit Flowminder produces the analysis using aggregated and anonymized mobile-phone records.
- Vodacom, Congo's largest operator, provides the data free of charge.
Health officials battling the Ebola outbreak in eastern Democratic Republic of Congo are employing anonymized mobile-phone data to map population movements and identify areas at risk of future spread. This novel approach, described by the World Health Organization (WHO) as unprecedented for an Ebola response, aims to optimize the deployment of limited surveillance and response resources.
The current outbreak, Congo's 17th, is caused by the Bundibugyo species of Ebola, for which there are no approved vaccines or treatments. As of the latest government data, more than 6,250 people have been infected and 3,039 have died since the outbreak was declared on May 15.
Traditional risk assessments typically focus on known outbreak hotspots and assume spread to adjacent areas. However, analyzing mobility data allows responders to identify risks in geographically distant locations that are connected through travel patterns. Olivier Le Polain, head of epidemiology and analytics for response at the WHO Health Emergencies Programme, stated that this method provides a more nuanced understanding of risk, particularly in regions like Ituri province, which is linked to significant mining and trade activities.
The analysis is conducted by the Swedish non-profit Flowminder, which uses aggregated and anonymized records generated when mobile phones connect to telecommunications networks. Researchers track these connections to estimate population travel patterns. Vodacom, Congo's largest mobile operator, provides this data free of charge. Flowminder founder Linus Bengtsson emphasized that the goal is to predict how infectious people move.
Flowminder's initial analysis in early June focused on the three areas where the outbreak is believed to have started. By the end of June, all ten destinations receiving the largest flows of travelers from these original outbreak areas had reported confirmed Ebola cases. As the virus spread, Flowminder expanded its analysis to include additional affected regions.
Particular attention was drawn to Kisangani, a major transport hub on the Congo River. Data indicated a significant risk of spread to Kisangani, prompting strengthened operations there before the first cases were detected. More recent studies have highlighted connections between Kisangani and Kinshasa, as well as other settlements and areas near the borders with the Central African Republic and South Sudan. Fifteen of the 50 areas most connected to Kisangani were in Kinshasa province, indicating a potential risk to the capital city.
The WHO continues to warn of the outbreak's potential to spread to Kinshasa and neighboring countries. A modeling exercise in late June estimated a 70% probability of a case being detected in South Sudan by the end of September.
A limitation of the current analysis is its reliance on data from a single telecom operator, Vodacom, which, despite being the largest in Congo, cannot capture the movements of users on rival networks. Efforts are underway to secure similar agreements with other operators to improve data coverage.