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COVID-19 Testimonial Series | SwissCovid

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SwissCovid app | Privacy by design


The following article is part of BioAlps’ testimonial series and was written by Prof Carmela Troncoso, Head of EPFL’s Security and Privacy Engineering Lab (SPRING). Our series aims to provide a platform for the different life sciences actors from western Switzerland, who are active in finding and developing solutions to fight against the new coronavirus, to share their experience. 


Presentation of SwissCovid’s COVID-19 related activities

In addition to hygiene measures and other recommendations, contact tracing is needed to slow transmission chains and combat the SARS-CoV-2 virus. Together with an international team, we developed the DP3T protocol. Because the data are stored on users’ phones rather than a central server, they cannot be misused while using this protocol. In addition, they are stored in a way that makes it impossible to automatically identify users who send out a COVID notification.

The DP3T protocol technologies were embedded in Google and Apple Exposure Notification API, and as such is the basis of the SwissCovid tracing app that was released to the general public on 25 June 2020.

The SwissCovid app automatically sends alerts to everyone who was within 1.5 meters of a COVID-19 patient for over 15 minutes (the exposure that scientists believe is necessary to become infected) – provided that the patient and the people around him or her have the app. Once a patient tests positive for the disease, he or she must enter his “COVID code” in the app; the notification sent to other users is anonymous. A data risk assessment carried out by MELANI, Switzerland’s Reporting and Analysis Centre for Information Assurance, concluded that the app provides an adequate level of data security, despite some vulnerabilities that researchers have identified.

This is privacy by design: we wanted to create a system that respects the need of citizens, which is not just to stop the coronavirus, but also to preserve freedom. So, we built an app that cannot be used for anything other than contact tracing – it cannot be used to know location, identities, or activities.


Impact of COVID-19 on the project

The project did not exist before the pandemic, as it was born as a response to this pandemic. The full project was carried out through online collaboration using messaging and videoconference application.

As soon as the pandemic is contained, there will be no need for this app anymore. That will be a good day.

All people involved in the design of DP3T and SwissCovid left their research agendas to focus on these projects.

As the autumn semester started at EPFL, a daily routine will probably be back and I will share my time between teaching and research, still mostly from home though. Of course, the work on the SwissCovid app continues.


Swiss government and academic institutions involvement in the project

The SwissCovid app was developed on behalf of and in cooperation with the FOPH by the Federal Office for Information Technology and Telecommunications FOITT, the Federal Institutes of Technology in Zurich (ETH) and Lausanne (EPFL) and the Swiss company Ubique.