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arXiv · 2112.03972

Viral replication dynamics could critically modulate vaccine effectiveness and should be accounted for when assessing new SARS-CoV-2 variants

Wan Yang·Jeffrey Shaman
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Abstract

In this article, we propose a theory to explain the reduction in vaccine effectiveness (VE) against the Delta SARS-CoV-2 variant and decreasing VE over time reported in recent studies. Using a model illustration, we show that in-host viral replication dynamics and delays in immune response could play a key role in VE. Given this, current laboratory approaches solely measuring reductions in neutralizing ability cannot fully represent the potential impact of new SARS-CoV-2 variants. We instead propose an alternative approach that incorporates viral replication dynamics into evaluations of SARS-CoV-2 variant impact on immunity and VE. This more robust assessment may better inform public health response to new variants like the newly detected Omicron variant.

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Wan Yang, Jeffrey Shaman. 2021-12-07. Viral replication dynamics could critically modulate vaccine effectiveness and should be accounted for when assessing new SARS-CoV-2 variants. https://arxiv.org/abs/2112.03972

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