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arXiv · 2302.01076

Duration of Transients in Outbreaks: When can Infectiousness be Estimated?

Adam Mielke·Lasse Engbo Christiansen
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Abstract

We investigate sub-leading orders of the classic SEIR-model using contact matrices from modeling of the Omicron and Delta variants of COVID-19 in Denmark. The goal of this is to illustrate when the growth rate, and by extension the infection transmission potential (basic or initial reproduction number), can be estimated in a new outbreak, e.g. after introduction of a new variant of a virus. In particular, we look at the time scale on which this happens in a realistic outbreak to guide future data collection. We find that as long as susceptible depletion is a minor effect, the transients are gone within around 3 weeks corresponding to about 4-5 times the incubation time. We also argue that this result generalizes to other airborne diseases in a fully mixed population.

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Adam Mielke, Lasse Engbo Christiansen. 2023-02-02. Duration of Transients in Outbreaks: When can Infectiousness be Estimated?. https://arxiv.org/abs/2302.01076

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