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bioRxiv · 10.1101/2021.12.06.471455

Loss of Neutralizing Antibody Response to mRNA Vaccination against SARS-CoV-2 Variants: Differing Kinetics and Strong Boosting by Breakthrough Infection

Evans, J. P.·Zeng, C.·Carlin, C.·Lozanski, G.·Saif, L. J.·Oltz, E. M.·Gumina, R. J.·Liu, S.-L.
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Abstract

The waning efficacy of SARS-CoV-2 vaccines combined with the continued emergence of variants resistant to vaccine-induced immunity has reignited debate over the need for booster vaccines. To address this, we examined the neutralizing antibody (nAb) response against four major SARS-CoV-2 variants--D614G, Alpha (B.1.1.7), Beta (B.1.351), and Delta (B.1.617.2)--in health care workers (HCWs) at pre-vaccination, post-first and post-second mRNA vaccine dose, and six months post-second mRNA vaccine dose. Neutralizing antibody titers against all variants, especially the Delta variant, declined dramatically from four weeks to six months post-second mRNA vaccine dose. Notably, SARS-CoV-2 infection enhanced vaccine durability, and mRNA-1273 vaccinated HCWs also exhibited ~2-fold higher nAb titers than BNT162b2 vaccinated HCWs. Together these results demonstrate possible waning of protection from infection against SARS-CoV-2 Delta variant based on decreased nAb titers, dependent on COVID-19 status and the mRNA vaccine received.

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Evans, J. P., Zeng, C., Carlin, C., Lozanski, G., Saif, L. J., Oltz, E. M., Gumina, R. J., Liu, S.-L.. 2021-12-07. Loss of Neutralizing Antibody Response to mRNA Vaccination against SARS-CoV-2 Variants: Differing Kinetics and Strong Boosting by Breakthrough Infection. https://doi.org/10.1101/2021.12.06.471455

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