Investigation of outbreak cases infected with the SARS-CoV-2 B.1.640 variant in a fully vaccinated elderly population, Normandy, France, November to December 2021 Mastrovito, Brice and Naimi, Chloé and Kouam, Leslie and Naudot, Xavier and Fournier, Lucie and Spaccaferri, Guillaume and Plantier, Jean-Christophe and Soares, Anaïs and De Oliveira, Fabienne and Gueudin, Marie and Jacomo, Véronique and Leroy, Céline and Moisan, Alice and Martel, Mélanie, Eurosurveillance, 27, 2200078 (2022), https://doi.org/10.2807/1560-7917.ES.2022.27.6.2200078