Bidirectional contact tracing could dramatically improve COVID-19 control
Name
s41467-020-20325-7.pdf
Description
Published version
Size
2.02 MB
Format
Adobe PDF
Checksum (MD5)
3089cfc5f5d35f450fab7c5ebb3a7c9c
Author(s)
Bradshaw, William J.
Alley, Ethan C.
Huggins, Jonathan H.
Lloyd, Alun L.
Esvelt, Kevin Michael
Date Issued
January 2021
Journal
Nature Communications
Publisher
Springer Science and Business Media LLC
Citation
Bradshaw, William J. et al. "Bidirectional contact tracing could dramatically improve COVID-19 control." Nature Communications 12, 1 (January 2021): 232 © 2021 The Author(s)
Version
Final published version
Abstract
Contact tracing is critical to controlling COVID-19, but most protocols only “forward-trace” to notify people who were recently exposed. Using a stochastic branching-process model, we find that “bidirectional” tracing to identify infector individuals and their other infectees robustly improves outbreak control. In our model, bidirectional tracing more than doubles the reduction in effective reproduction number (Reff) achieved by forward-tracing alone, while dramatically increasing resilience to low case ascertainment and test sensitivity. The greatest gains are realised by expanding the manual tracing window from 2 to 6 days pre-symptom-onset or, alternatively, by implementing high-uptake smartphone-based exposure notification; however, to achieve the performance of the former approach, the latter requires nearly all smartphones to detect exposure events. With or without exposure notification, our results suggest that implementing bidirectional tracing could dramatically improve COVID-19 control.
MIT Department
Massachusetts Institute of Technology. Media Laboratory
Terms of Use
Creative Commons Attribution 4.0 International license
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1038/s41467-020-20325-7
