Limited spread of a rare spike E484K-harboring SARS-CoV-2 in Marseille, France.

We detected SARS-CoV-2 of PANGO lineage R.1 with the spike substitution E484K in three patients. Eleven other sequences in France and 8,831 worldwide were available from GISAID, 92% originating from Japan. The three genome sequences from our institute were phylogenetically closest to another from Guinea-Conakry, where one of the patients had travelled. These viruses did not exhibit any unusual features in cell culture. Spike structural predictions indicated a 1.3-time higher transmissibility index than for the globally spread B.1.1.7 variant but also an affinity loss for gangliosides that might have slowed dissemination. The spread of new SARS-CoV-2 mutants/variants is still not well understood and therefore difficult to predict, and this hinders implementation of effective preventive measures, including adapted vaccines.