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Digital herd immunity and COVID-19

Bulchandani, Vir Bannerjee and Shivam, Saumya and Moudgalya, Sanjay and Sondhi, S. L. (2021) Digital herd immunity and COVID-19. Physical Biology, 18 (4). Art. No. 045004. ISSN 1478-3967. doi:10.1088/1478-3975/abf5b4.

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A population can be immune to epidemics even if not all of its individual members are immune to the disease, so long as sufficiently many are immune—this is the traditional notion of herd immunity. In the smartphone era a population can be immune to epidemics even if not a single one of its members is immune to the disease—a notion we call "digital herd immunity'', which is similarly an emergent characteristic of the population. This immunity arises because contact-tracing protocols based on smartphone capabilities can lead to highly efficient quarantining of infected population members and thus the extinguishing of nascent epidemics. When the disease characteristics are favorable and smartphone usage is high enough, the population is in this immune phase. As usage decreases there is a novel "contact-tracing phase transition'' to an epidemic phase. We present and study a simple branching-process model for COVID-19 and show that digital immunity is possible regardless of the proportion of non-symptomatic transmission.

Item Type:Article
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URLURL TypeDescription Paper
Bulchandani, Vir Bannerjee0000-0002-7438-5711
Shivam, Saumya0000-0002-7957-153X
Additional Information:© 2021 IOP Publishing Ltd. Received 26 February 2021; Revised 23 March 2021; Accepted 7 April 2021; Published 23 June 2021. We would like to thank Professor K. VijayRaghavan for interesting us in this question and for discussions of India's Aarogya Setu contact tracing app, Professor Bryan Grenfell for sharing his wisdom regarding epidemiology at an extremely hectic time and Dr. Shoibal Chakravarty for continuing discussions on all aspect of India's COVID-19 challenges.
Issue or Number:4
Record Number:CaltechAUTHORS:20210409-145940364
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Official Citation:Vir B Bulchandani et al 2021 Phys. Biol. 18 045004
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:108681
Deposited By: Tony Diaz
Deposited On:13 Apr 2021 22:12
Last Modified:12 Jul 2022 19:52

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