Green indicates a clean bill of health, yellow means the bearer may have visited a high-risk virus area within the past 14 days and is subject to closer inspection, while red indicates quarantine is necessary.
There has been scant public explanation of how the information is obtained, other than vague references to big data, presumably by tracking a person’s history of online payments, which have rapidly replaced cash in China.
Government announcements have made clear that the coding system will remain in use in some form even after the pandemic subsides.
Europe is also searching for tech options as it scrambles to halt spiraling infections.
On Wednesday a team of experts at the University of Oxford announced they were working with several European governments to explore an app for instant contact tracing that could be deployed with “appropriate ethical considerations”.
“Current strategies are not working fast enough to intercept the transmission of coronavirus,” said Professor Christophe Fraser from the university’s Big Data Institute.
“To effectively tackle this pandemic we need to harness 21st century technology.”
by Jerome Taylor and AFP reporters