Bayesian Re-Analysis of the Phylogenetic Topology of Early SARS-CoV-2 Case Sequences

Michael B. Weissman

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arXiv · 2510.01484

Bayesian Re-Analysis of the Phylogenetic Topology of Early SARS-CoV-2 Case Sequences

Michael B. Weissman

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Abstract

A much-cited 2022 paper by Pekar et al. claimed that Bayesian analysis of the molecular phylogeny of early SARS-CoV-2 cases indicated that it was more likely that two successful introductions to humans had occurred than that just one had. Here I show that after correcting a fundamental error in Bayesian reasoning the results in that paper give larger likelihood for a single introduction than for two.

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Michael B. Weissman. 2025-10-01. Bayesian Re-Analysis of the Phylogenetic Topology of Early SARS-CoV-2 Case Sequences. https://arxiv.org/abs/2510.01484

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