Using Digital Surveillance Tools for Near Real-Time Mapping of the Risk of International Infectious Disease Spread: Ebola as a Case Study

Sangeeta Bhatia; Britta Lassmann; Emily Cohn; Malwina Carrion; Moritz U.G. Kraemer; Mark Herringer; John Brownstein; Larry Madoff; Anne Cori; Pierre Nouvellet

In the past three decades, the internet has grown at a staggering pace, with approximately half of the world's population accessing internet in 2017 [8] . The rapid growth of the internet has fostered a corresponding increase in tools for internet based disease detection and monitoring that lie at the other end of the spectrum. Digital disease surveillance consists of monitoring online information sources to collate relevant information about diseases. The sources of information can be formal such as advisories posted by a ministry of health, or informal such as news media items, blogs or tweets. Digital surveillance makes data collection less expensive and time consuming but the acquired data often contain more noise than those collected through traditional public health surveillance. While traditional surveillance systems report on select pathogens and depend on a well-functioning public health infrastructure, digital surveillance in contrast typically monitor a wide range of pathogens using little to no additional infrastructure. Thus, digital surveillance tools can play a significant role in the rapid recognition of public health emergencies [9, 10] .