Introductions and early spread of SARS-CoV-2 in France, 24 January to 23 March 2020

Abstract

Following SARS-CoV-2 emergence in China, a specific surveillance was implemented in France. Phylogenetic analysis of sequences retrieved through this surveillance suggests that detected initial introductions, involving non-clade G viruses, did not seed local transmission. Nevertheless, identification of clade G variants subsequently circulating in the country, with the earliest from a patient who neither travelled to risk areas nor had contact with travellers, suggests that SARS-CoV-2 might have been present before the first recorded local cases.