Science in times of uncertainty: the origin of SARS-CoV-2

Florence Débarre

Institut d’Écologie et des Sciences de l’Environnement, Paris

florence.debarre@sorbonne-universite.fr

Link to seminar: https://umontpellier-fr.zoom.us/webinar/register/WN_jeeHFgmnTayrvaz4q_acoQ

** Interactive polls will be proposed during the seminar, please bring your phone to participate!**

In the last days of December 2019, clusters of cases of unexplained pneumonia were detected in hospitals in Wuhan, China. Three years later, the precise origin of what became the Covid-19 pandemic is still not known with certainty. This gap was filled in part by numerous conspiracy theories, sometimes echoed in reliable outlets.

In the first part of the talk, I will present the current state of our understanding of the origin of SARS-CoV-2. I will show that all facts and data point to a natural origin linked to the Huanan seafood market, while the lab origin hypothesis rests on speculations.

I will then present recent work by our team, providing a population dynamics-based methodological framework to date the emergence of an outbreak, and its applications to the emergence of Covid-19.

Time permitting, in a final part, I will dissect a couple of conspiracy theories, and show how they can be born out of the juxtaposition of multiple mundane events, inaccuracies, or honest errors.

References:
S. Jijón, P. Czuppon, F. Blanquart, F. Débarre Using early detection data to estimate the date of emergence of an epidemic outbreak. medRxiv 2023.01.09.23284284; doi: https://doi.org/10.1101/2023.01.09.23284284

P. Czuppon, E. Schertzer, F. Blanquart, F. Débarre (2021) The stochastic dynamics of early epidemics: probability of establishment, initial growth rate, and infection cluster size at first detection Journal of the Royal Society Interface  https://doi.org/10.1098/rsif.2021.0575