SARS-CoV-2 Omicron's latest subvariant BQ.1.1 reveals extraordinary immune evasion potential in opposition to vaccine sera

By Neha MathurNov 4 2022Reviewed by Aimee Molineux

In a current examine posted to the bioRxiv* preprint server, researchers pursued immunological proof of why BQ.1.1 prevalence swiftly elevated in areas the place Omicron BA.5 was dominant in america (US).

Background

Research have proven that Omicron BQ.1.1 instances quickly elevated in frequency within the US, and Omicron BA.5 instances declined to lower than half, the place not way back, Omicron BA.5 was the dominant extreme acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variant. Thus, it’s essential to find out how BQ.1.1 evades neutralizing antibodies (nAbs) induced by coronavirus illness 2019 (COVID-19) vaccination and SARS-CoV-2 an infection.

In regards to the examine

Within the current examine, researchers assessed nAb titers in 16 people who had been vaccinated and boosted with the monovalent mRNA BNT162b2 vaccine in 2021. Subsequent, they evaluated nAb titers in 15 people who obtained the monovalent mRNA boosters in 2022. Moreover, 18 bivalent mRNA booster recipients, most of whom obtained three vaccine doses, though some had additionally obtained two or 4 COVID-19 vaccine doses.

Examine findings

Following the monovalent BNT162b2 increase, median nAb titers to WA1/2020, BA.5, BF.7, BA.2.75.2, and BQ.1.1 had been 45, 695, 887, 595, 387, and 261, respectively. The authors famous that the median nAb titers in opposition to BQ.1.1 had been a lot diminished than the median nAb titers in opposition to WA1/2020 and BA.5 by elements of 175 and three, respectively.

In comparison with the uninfected 2021 cohort, most had been probably contaminated in these cohorts, though the documented charges for SARS-CoV-2 Omicron infections had been as little as 33%. Additionally, WA1/2020 and Omicron nAb titers had been larger within the two 2022 cohorts even earlier than boosting. After boosting, their median NAb titers to WA1/2020, BA.5, BF.7, BA.2.75.2, and BQ.1.1 had been 40,515, 3693, 2399, 883, and 508, respectively.

Conclusions

The examine outcomes confirmed that in comparison with BA.5, each BA.2.75.2 and BQ.1.1 escaped nAbs-elicited by prior an infection and vaccination extra successfully. The impact was most pronounced for BQ.1.1, whose nAb titers had been decrease than BA.5 by an element of seven throughout examine cohorts.

These findings current an immunological rationalization for the immediate surge in BQ.1.1 prevalence in areas the place BA.5 was dominant within the US, which has implications for each vaccine and pure immunity. Additionally, it places into perspective how the presence of the R346T mutation in a number of new Omicron subvariants is probably going a consequence of convergent evolution.

*Necessary discover

bioRxiv publishes preliminary scientific experiences that aren’t peer-reviewed and, subsequently, shouldn’t be thought to be conclusive, information scientific follow/health-related conduct, or handled as established info.