Durability of Neutralization Against Omicron Subvariants after Vaccination and Breakthrough Infection

Abstract

Booster immunizations and breakthrough infections can elicit SARS-CoV-2 Omicron subvariants neutralizing activity. However, the durability of the neutralization response is not known. We characterized the sensitivity of BA.1, BA.2, BA.2.75, BA.4/BA.5, and BF.7 to neutralizing antibodies from vaccination, hybrid immunity, and breakthrough infections 4-7 months after vaccination and infection. We show that two-dose CoronaVac or a third-dose ZF2001 booster elicits limited neutralization against Omicron subvariants 6 months after vaccination. However, hybrid immunity as well as Delta, BA.1, and BA.2 breakthrough infections induced long-term persistence of the antibody response, and over 70% of sera neutralized BA.1, BA.2, BA.4/BA.5, and BF.7. BA.2.75 is more resistant to hybrid immunity and breakthrough infection sera than BA.1, BA.2 and BF.7. BF.7 and BA.4/BA.5 are comparably neutralized by hybrid immunity and breakthrough infection sera. These data highlight additional vaccination in CoronaVac- or ZF2001-vaccinated individuals and provide insight into the durability of neutralization against Omicron subvariants.

Funding Information: This work was supported by grants from the National Natural Science Foundation of China (82273692, 92169207, and 81621005) and the Beijing Natural Science Foundation (L202038).

Declaration of Interests: We declare no competing interests.

Ethics Approval Statement: This study was conducted following the Declaration of Helsinki and approved by the Institutional Review Board of the Beijing Institute of Microbiology and Epidemiology (IRB number: AF/SC-08/02.60 and AF/SC-08/02.124). All participants provided written consent.

Keywords: Booster vaccination, hybrid immunity, breakthrough infection, Omicron subvariants, neutralization