In December, 2019, a local outbreak of pneumonia of initially unknown cause was detected
in Wuhan (Hubei, China), and was quickly determined to be caused by a novel coronavirus,
1
namely severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The outbreak
has since spread to every province of mainland China as well as 27 other countries
and regions, with more than 70 000 confirmed cases as of Feb 17, 2020.
2
In response to this ongoing public health emergency, we developed an online interactive
dashboard, hosted by the Center for Systems Science and Engineering (CSSE) at Johns
Hopkins University, Baltimore, MD, USA, to visualise and track reported cases of coronavirus
disease 2019 (COVID-19) in real time. The dashboard, first shared publicly on Jan
22, illustrates the location and number of confirmed COVID-19 cases, deaths, and recoveries
for all affected countries. It was developed to provide researchers, public health
authorities, and the general public with a user-friendly tool to track the outbreak
as it unfolds. All data collected and displayed are made freely available, initially
through Google Sheets and now through a GitHub repository, along with the feature
layers of the dashboard, which are now included in the Esri Living Atlas.
The dashboard reports cases at the province level in China; at the city level in the
USA, Australia, and Canada; and at the country level otherwise. During Jan 22–31,
all data collection and processing were done manually, and updates were typically
done twice a day, morning and night (US Eastern Time). As the outbreak evolved, the
manual reporting process became unsustainable; therefore, on Feb 1, we adopted a semi-automated
living data stream strategy. Our primary data source is DXY, an online platform run
by members of the Chinese medical community, which aggregates local media and government
reports to provide cumulative totals of COVID-19 cases in near real time at the province
level in China and at the country level otherwise. Every 15 min, the cumulative case
counts are updated from DXY for all provinces in China and for other affected countries
and regions. For countries and regions outside mainland China (including Hong Kong,
Macau, and Taiwan), we found DXY cumulative case counts to frequently lag behind other
sources; we therefore manually update these case numbers throughout the day when new
cases are identified. To identify new cases, we monitor various Twitter feeds, online
news services, and direct communication sent through the dashboard. Before manually
updating the dashboard, we confirm the case numbers with regional and local health
departments, including the respective centres for disease control and prevention (CDC)
of China, Taiwan, and Europe, the Hong Kong Department of Health, the Macau Government,
and WHO, as well as city-level and state-level health authorities. For city-level
case reports in the USA, Australia, and Canada, which we began reporting on Feb 1,
we rely on the US CDC, the government of Canada, the Australian Government Department
of Health, and various state or territory health authorities. All manual updates (for
countries and regions outside mainland China) are coordinated by a team at Johns Hopkins
University.
The case data reported on the dashboard aligns with the daily Chinese CDC
3
and WHO situation reports
2
for within and outside of mainland China, respectively (figure
). Furthermore, the dashboard is particularly effective at capturing the timing of
the first reported case of COVID-19 in new countries or regions (appendix). With the
exception of Australia, Hong Kong, and Italy, the CSSE at Johns Hopkins University
has reported newly infected countries ahead of WHO, with Hong Kong and Italy reported
within hours of the corresponding WHO situation report.
Figure
Comparison of COVID-19 case reporting from different sources
Daily cumulative case numbers (starting Jan 22, 2020) reported by the Johns Hopkins
University Center for Systems Science and Engineering (CSSE), WHO situation reports,
and the Chinese Center for Disease Control and Prevention (Chinese CDC) for within
(A) and outside (B) mainland China.
Given the popularity and impact of the dashboard to date, we plan to continue hosting
and managing the tool throughout the entirety of the COVID-19 outbreak and to build
out its capabilities to establish a standing tool to monitor and report on future
outbreaks. We believe our efforts are crucial to help inform modelling efforts and
control measures during the earliest stages of the outbreak.