Application of Digital Contact Tracing via Mobile Phones

written/edited by Aashman Chalishazar

“Safety is not an intellectual exercise to keep us in work. It is a matter of life and death. It is the sum of our contributions to safety management that determines whether the people we work with life or death.”

-Sir Brian Appleton

Would anyone have imagined that in 2020, a mystery virus would halt the globalized world in its tracks? Millions of people have confined into their homes to save themselves from the deadly virus. Global economies have come crashing down resulting in trepidation and uncertainty everywhere. Hence with the colossal threat of infections looming high over everyone from the SARS-CoV-2, it becomes immensely important for governments to come up with effective methods to protect its citizens from the virus using modern technology, which is accessible to everyone. Research and development towards this goal resulted in the development of a method called ‘Digital Contact Tracing’ via apps that can be installed in smartphones.

What is Digital Contact Tracing?

Digital contact tracing is a method that takes advantage of Bluetooth and GPS in mobile devices to determine contact between an infected patient and a user.

Such an app uses low- energy Bluetooth beacon signals to determine when a phone is near another phone that also has the app installed. Both phones exchange unique anonymized IDs, which are then stored in an encrypted form on the other user’s phone. Each user’s phone has a log of all IDs, representing all the people close enough to infect the user.

If a user gets infected with COVID-19, he/she will be asked to give the contact tracers access to the app data for a list of anonymized IDs that the infected user’s phone has been close to. The decrypted anonymized IDs from the phones of those who had been around the infected person quickly helps the contact tracers to identify and alert people who are at a high risk of infection.

Those alerted would be advised to quarantine themselves as they could have possibly been exposed to the virus. The movements of the infected person over the previous two weeks are tracked via GPS and made available for everyone to see. The app would enable users to reveal the whereabouts of an infected person and know how recently the infected person went to a given place.

This information lets people know if they crossed paths with an infected person, and they can get tested for the virus. If one of those people is infected, the whole process of contact tracing starts all over again.

Many countries throughout the world have attempted to use digital contact tracing to fight the virus.

South Korea has successfully implemented these methods, along with aggressive testing, and has been able to flatten the curve drastically. The Aarogya Setu app has a similar function in India. It has registered over 50 Million users within weeks of being launched. Singapore has launched the TraceTogether app to assist its people.

Concerns over privacy

A major drawback of such contact tracing apps is that they compromise the privacy of citizens. Only the government can have access to user data, but many countries do not have strong data protection laws in place to keep a check on companies from misusing user data at present or in the future. Therefore, it eventually boils down to the trust that citizens have in their government and whether they are willing to trade off their privacy to gain control over a pandemic.

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