Epidemic Exposure Tracking With Wearables: A Machine Learning Approach to Contact Tracing

The recent pandemic revealed weaknesses in several areas, including the limited capacity of public health systems for efficient case tracking and reporting. In the post-pandemic era, it is essential to be ready and provide not only preventive measures, but also effective digital strategies and solutions to protect our population from future outbreaks. This work presents a contact tracing solution based on wearable devices to track epidemic exposure. Our proximity-based privacy-preserving contact tracing (P3CT) integrates: 1) the Bluetooth Low Energy (BLE) technology for reliable proximity sensing, 2) a machine-learning approach to classify the exposure risk of a user, and 3) an ambient signature protocol for preserving the user's identity. Proximity sensing exploits the signals emitted from a smartwatch to estimate users' interaction, in terms of distance and duration. Supervised learning is then used to train four classification models to identify the exposure risk of a user with respect to a patient diagnosed with an infectious disease. Finally, our proposed P3CT protocol uses ambient signatures to anonymize the infected patient's identity. Extensive experiments demonstrate the feasibility of our proposed solution for real-world contact tracing problems. The large-scale dataset consisting of the signal information collected from the smartwatch is available online. According to experimental results, wearable devices along with machine learning models are a promising approach for epidemic exposure notification and tracking.