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bioRxiv · 10.1101/2021.12.20.473584

Neutralization against Omicron SARS-CoV-2 from previous non-Omicron infection

Zou, j.·Xia, H.·Xie, X.·Kurhade, C.·Machado, R. R.·Weaver, S. C.·Ren, P.·Shi, P.-Y.
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Abstract

The explosive spread of the Omicron SARS-CoV-2 variant underscores the importance of analyzing the cross-protection from previous non-Omicron infection. We developed a high-throughput neutralization assay for Omicron SARS-CoV-2 by engineering the Omicron spike gene into an mNeonGreen USA-WA1/2020 SARS-CoV-2 (isolated in January 2020). Using this assay, we determined the neutralization titers of patient sera collected at 1- or 6-months after infection with non-Omicron SARS-CoV-2. From 1- to 6-month post-infection, the neutralization titers against USA-WA1/2020 decreased from 601 to 142 (a 4.2-fold reduction), while the neutralization titers against Omicron-spike SARS-CoV-2 remained low at 38 and 32, respectively. Thus, at 1- and 6-months after non-Omicron SARS-CoV-2 infection, the neutralization titers against Omicron were 15.8- and 4.4-fold lower than those against USA-WA1/2020, respectively. The low cross-neutralization against Omicron from previous non-Omicron infection supports vaccination of formerly infected individuals to mitigate the health impact of the ongoing Omicron surge.

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Zou, j., Xia, H., Xie, X., Kurhade, C., Machado, R. R., Weaver, S. C., Ren, P., Shi, P.-Y.. 2021-12-22. Neutralization against Omicron SARS-CoV-2 from previous non-Omicron infection. https://doi.org/10.1101/2021.12.20.473584

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