Cross-neutralizing activity against Omicron could be obtained in SARS-CoV-2 convalescent patients who received two doses of mRNA vaccination

Abstract

The SARS-CoV-2 variant Omicron is now under investigation. We evaluated cross-neutralizing activity against Omicron in COVID-19 convalescent patients who had received two doses of an mRNA vaccination. Surprisingly and interestingly, after the second vaccination, the subject neutralizing antibody titers including that against Omicron all became seropositive, and significant fold-increases were seen regardless of the subject disease severity. Our findings thus demonstrate that at least two doses of mRNA vaccination to SARS-CoV-2 convalescent patients can induce cross-neutralizing activity against Omicron.