Population Bottlenecks and Intra-host Evolution During Human-to-Human Transmission of SARS-CoV-2

Front Med (Lausanne). 2021 Feb 15:8:585358. doi: 10.3389/fmed.2021.585358. eCollection 2021.

Abstract

The emergence of the novel human coronavirus, SARS-CoV-2, causes a global COVID-19 (coronavirus disease 2019) pandemic. Here, we have characterized and compared viral populations of SARS-CoV-2 among COVID-19 patients within and across households. Our work showed an active viral replication activity in the human respiratory tract and the co-existence of genetically distinct viruses within the same host. The inter-host comparison among viral populations further revealed a narrow transmission bottleneck between patients from the same households, suggesting a dominated role of stochastic dynamics in both inter-host and intra-host evolutions.

Keywords: SARS-CoV-2; evolution; human to human transmission; intra-host variation; population bottleneck.