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arXiv · 2103.06427

Recursive contact tracing in Reed-Frost epidemic models

Saumya Shivam·Vir B. Bulchandani·S. L. Sondhi
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Abstract

We introduce a Reed-Frost epidemic model with recursive contact tracing and asymptomatic transmission. This generalizes the branching-process model introduced by the authors in a previous work [arxiv:2004.07237] to finite populations and general contact networks. We simulate the model numerically for two representative examples, the complete graph and the square lattice. On both networks, we observe clear signatures of a contact-tracing phase transition from an "epidemic phase" to an "immune phase" as contact-network coverage is increased. We verify that away from the singular line of perfect tracing, the finite-size scaling of the contact-tracing phase transition on each network lies in the corresponding percolation universality class. Finally, we use the model to quantify the efficacy of recursive contact-tracing in regimes where epidemic spread is not contained.

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Saumya Shivam, Vir B. Bulchandani, S. L. Sondhi. 2021-03-11. Recursive contact tracing in Reed-Frost epidemic models. https://doi.org/10.1088/1478-3975%2Fac0fd1

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