Impact of Using Soft Exposure Thresholds in Automatic Contact Tracing

Published

December 21, 2022

Author(s)

Kamran Sayrafian, Brian D. Cloteaux, Vladimir Marbukh

Abstract

Current automatic exposure notification apps primarily operate based on hard distance/time threshold guidelines (e.g., 2 m/15 min in the United States) to determine exposures due to close contacts. However, the possibility of virus transmission through inhalation for distances over the specified distance threshold might necessitate consideration of soft distance/time thresholds to accommodate all transmission scenarios. In this paper, using a simplifying approximation on the instantaneous rate of the viral exposure versus distance, we extend the definition of "contact" by proposing a soft distance/time threshold which includes the possibility of getting exposed at any distance (within certain limits) around an infected person. We then analyze the performance of automatic exposure notification with Bluetooth-based proximity detection by comparing the exposure results when soft or hard thresholds are used. This study is done through an agent-based simulation platform that allows for a comprehensive analysis using several system parameters. By tuning the parameters of the proposed soft thresholds, a more accurate determination of possible exposures at any distance would be possible. This would enhance the effectiveness of an automatic contact tracing system. Our results indicate the noticeable impact of using the soft distance/time threshold on the exposure detection accuracy.

Conference Dates

October 17-19, 2022

Conference Location

Genoa, IT

Conference Title

2022 IEEE International Conference on E-health Networking, Application & Services (HealthCom)

Pub Type

Conferences

Download Paper

https://doi.org/10.1109/HealthCom54947.2022.9982790

Local Download

Keywords

Proximity Detection, Bluetooth, Exposure Determination, COVID-19, Contact Tracing

Citation

Sayrafian, K. , Cloteaux, B. and Marbukh, V. (2022), Impact of Using Soft Exposure Thresholds in Automatic Contact Tracing, 2022 IEEE International Conference on E-health Networking, Application & Services (HealthCom), Genoa, IT, [online], https://doi.org/10.1109/HealthCom54947.2022.9982790, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=935550 (Accessed October 17, 2025)