Dynamics of viral shedding during ancestral or Omicron BA.1 SARS-CoV-2 infection and enhancement of pre-existing immunity during breakthrough infections

Omicron variant is circulating in the presence of a globally acquired immunity unlike the ancestral SARS-CoV-2 isolate. Herein, we investigated the normalized viral load dynamics and viral culture status in 44 fully vaccinated healthcare workers (HCWs) infected with the Omicron BA.1 variant. Viral load dynamics of 38 unvaccinated HCWs infected with the 20A variant during the first pandemic wave was also studied. We then explored the impact of Omicron infection on pre-existing immunity assessing anti-RBD IgG levels, neutralizing antibody titres against 19A, Delta and Omicron isolates, as well as IFN-γ release following cell stimulation with SARS-CoV-2 peptides. We reported that two weeks after diagnosis a greater proportion of HCWs infected with 20A (78.9%, 15/19) than with Omicron BA.1 (44.7%, 17/38; p = 0.02) were still positive by RT-qPCR. We found that Omicron breakthrough infections led to an overall enhancement of vaccine-induced humoral and cellular immunity as soon as a median [interquartile range] of 8 [7-9] days post symptom onset. Among samples with similar high viral loads, non-culturable samples exhibited higher neutralizing antibody titres and anti-RBD IgG levels than culturable samples. Additionally, Omicron infection led to an enhancement of antibodies neutralization capacity against other SARS-CoV-2 isolates. Taken together, the results suggest that Omicron BA.1 vaccine breakthrough infection is associated with a faster viral clearance than that of the ancestral SARS-CoV-2, in addition this new variant leads to a rapid enhancement of the humoral response against multiple SARS-CoV-2 variants, and of the cellular response.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:11

Enthalten in:

Emerging microbes & infections - 11(2022), 1 vom: 01. Dez., Seite 2423-2432

Sprache:

Englisch

Beteiligte Personen:

Saade, Carla [VerfasserIn]
Brengel-Pesce, Karen [VerfasserIn]
Gaymard, Alexandre [VerfasserIn]
Trabaud, Mary-Anne [VerfasserIn]
Destras, Gregory [VerfasserIn]
Oriol, Guy [VerfasserIn]
Cheynet, Valérie [VerfasserIn]
Debombourg, Marion [VerfasserIn]
Mokdad, Bouchra [VerfasserIn]
Billaud, Geneviève [VerfasserIn]
Oblette, Antoine [VerfasserIn]
Créhalet, Hervé [VerfasserIn]
Giannoli, Jean-Marc [VerfasserIn]
Garrigou, Christine [VerfasserIn]
Generenaz, Laurence [VerfasserIn]
Compagnon, Christelle [VerfasserIn]
Boibieux, André [VerfasserIn]
Lina, Bruno [VerfasserIn]
Morfin, Florence [VerfasserIn]
Pozzetto, Bruno [VerfasserIn]
Josset, Laurence [VerfasserIn]
Trouillet-Assant, Sophie [VerfasserIn]
Bal, Antonin [VerfasserIn]

Links:

Volltext

Themen:

Antibodies, Neutralizing
Antibodies, Viral
Immunoglobulin G
Infectiousness
Journal Article
Omicron
SARS-CoV-2
Vaccine-immunity
Viral Vaccines
Viral culture
Viral shedding

Anmerkungen:

Date Completed 27.10.2022

Date Revised 09.05.2023

published: Print

Citation Status MEDLINE

doi:

10.1080/22221751.2022.2122578

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM346153891