Low rate of transmission to triple-vaccinated contacts of an imported case of SARS-CoV-2 omicron infection: a contact tracing study in Israel

On 26 November 2021, the World Health Organization desig- nated SARS-CoV-2 B.1.1.529 (Omicron) a variant of concern. By 26 November, 4.1 million (44%) Israelis had received a third dose (booster) of the BNT16262 COVID-19 vaccine. On 28 November, Omicron was reported in Israel. We describe findings from a contact tracing investigation of a healthcare worker with confirmed Omicron infection conducted at Sheba Medical Center (SMC).