key: cord-0720109-9aey4mwp
authors: Dimeglio, Chloé; Migueres, Marion; Chapuy-Regaud, Sabine; Da-Silva, Isabelle; Jougla, Isabelle; Pradere, Claire; Porcheron, Marion; Martin-Blondel, Guillaume; Lougarre, Catherine; Herin, Fabrice; Izopet, Jacques
title: Comparative effects of mRNA vaccine booster and natural Omicron infection on the neutralizing antibody response
date: 2022-05-07
journal: J Infect
DOI: 10.1016/j.jinf.2022.05.001
sha: 80c9079415867d71ef9e9d46f0c95d04570974e9
doc_id: 720109
cord_uid: 9aey4mwp

nan

in populations whose immunity is due to a prior infection and/or vaccination [3] , while other studies indicate that Omicron overcomes the immunity provided by vaccination and/or infection with an earlier variant [4] . Public health policies can benefit from knowledge of the immune responses elicited by vaccination and natural infection.

We analyzed the neutralizing antibody responses of 115 individuals matched for age and sex: 23 were unvaccinated and had been infected with Omicron, 23 had been vaccinated with two doses and had never been infected, 23 had been infected with Omicron after two doses of vaccine, 23 had received a mRNA vaccine booster (third dose) and had no infection, 23 had been infected with Omicron after a mRNA vaccine boost. Infections were detected using a nucleic-acid amplification method (Aptima TM , Hologic, USA) [5] and SARS-CoV-2 RNA was sequenced using single-molecule real-time sequencing (Pacific Biosciences, USA) [6] . These data indicate that a SARS-CoV-2 Omicron infection elicits a stronger immune response against Omicron than a full (2 dose) course of vaccination. The booster dose increased the neutralizing antibody response of the 2-dose-vaccinated subjects but it remained below the level conferred by an Omicron infection.

Our findings could, despite the small sample size, help optimize future vaccination strategies.

No specific funding

Regular and booster vaccination with inactivated vaccines enhance the neutralizing activity against Omicron variant both in the breakthrough infections and vaccinees

Vaccine Effectiveness of Three vs. Two Doses of SARS-CoV-2 mRNA Vaccines in a High Risk National Population

Increased risk of SARS-CoV-2 reinfection associated with emergence of Omicron in South Africa

Breakthrough infections with SARS-CoV-2 omicron despite mRNA vaccine booster dose

Evaluation of the Aptima transcription-mediated amplification assay (Hologic(R)) for detecting SARS-CoV-2 in clinical specimens

Prediction of SARS-CoV-2 Variant Lineages Using the S1-Encoding Region Sequence Obtained by PacBio Single-Molecule Real-Time Sequencing. Viruses

FIGURE LEGEND Figure 1: Neutralizing antibody titers: influence of infection status and vaccination schedule

The English text was edited by Dr Owen Parkes.

The authors declare no conflict of interest