Protection against Reinfection with the Omicron BA.2.75 Subvariant

Abstract

The BA.2.75 sublineage of the B.1.1.529 (omicron) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may escape neutralizing antibodies. The BA.2.75 sublineage (primarily the BA.2.75.2 subvariant) became the predominant sublineage in Qatar by September 10, 2022 (Section S1 and Fig. S1 in the Supplementary Appendix, available with the full text of this letter at NEJM.org). We estimated the effectiveness of previous infection with SARS-CoV-2 in preventing reinfection with BA.2.75 using a test-negative, case–control study design (Section S2).1