K-Level Contact Tracing Using Mesh Block-Based Trajectories for Infectious Diseases

Abstract

Contact tracing is a method of identifying people who may have come into contact with an infected person during a virus incubation time. Standard contact tracing is performed to identify only the first level of exposures, whereas in reality, exposures can occur across multiple levels. Multi-level contact tracing can reveal a wider range of objects which contribute to the spread of the virus. This paper proposes a k-Level Contact Tracing Query (kL-CTQ) to reveal a broader range of objects which have possibly been exposed to pathogens. To minimize manual location tracing while preserving the user’s privacy, we propose a mesh block sequence (MBS) method where the trajectories are transformed into an MBS before being shared with health authorities. While our simulation uses an Australian administrative region structure, this method is applicable in countries which implement similar administrative hierarchical building blocks.