Stochasticity and heterogeneity in the transmission dynamics of SARS-CoV-2

TL;DR

This paper highlights the stochastic nature of SARS-CoV-2 transmission, emphasizing the importance of super-spreading events and advocating targeted interventions to control outbreaks.

Contribution

It provides a detailed analysis of super-spreading events and their impact on COVID-19 transmission dynamics, offering recommendations for targeted control measures.

Findings

Super-spreading events significantly drive COVID-19 outbreaks.

Transmission is highly stochastic and dominated by few individuals.

Targeted interventions can effectively contain outbreaks.

Abstract

SARS-CoV-2 causing COVID-19 disease has moved rapidly around the globe, infecting millions and killing hundreds of thousands. The basic reproduction number, which has been widely used and misused to characterize the transmissibility of the virus, hides the fact that transmission is stochastic, is dominated by a small number of individuals, and is driven by super-spreading events (SSEs). The distinct transmission features, such as high stochasticity under low prevalence, and the central role played by SSEs on transmission dynamics, should not be overlooked. Many explosive SSEs have occurred in indoor settings stoking the pandemic and shaping its spread, such as long-term care facilities, prisons, meat-packing plants, fish factories, cruise ships, family gatherings, parties and night clubs. These SSEs demonstrate the urgent need to understand routes of transmission, while posing an opportunity that outbreak can be effectively contained with targeted interventions to eliminate SSEs. Here, we describe the potential types of SSEs, how they influence transmission, and give recommendations for control of SARS-CoV-2.