tetano
Editor, Senior Moderator
Viruses
. 2022 Jun 9;14(6):1257.
doi: 10.3390/v14061257.
High Incidence of SARS-CoV-2 Variant of Concern Breakthrough Infections Despite Residual Humoral and Cellular Immunity Induced by BNT162b2 Vaccination in Healthcare Workers: A Long-Term Follow-Up Study in Belgium
Bas Calcoen[SUP] 1 [/SUP], Nico Callewaert[SUP] 2 [/SUP], Aline Vandenbulcke[SUP] 1 [/SUP], Winnie Kerstens[SUP] 3 [/SUP], Maya Imbrechts[SUP] 4 [/SUP], Thomas Vercruysse[SUP] 3 [/SUP], Kai Dallmeier[SUP] 5 [/SUP], Johan Van Weyenbergh[SUP] 6 [/SUP], Piet Maes[SUP] 6 [/SUP], Xavier Bossuyt[SUP] 7 8 [/SUP], Dorinja Zapf[SUP] 9 [/SUP], Kersten Dieckmann[SUP] 9 [/SUP], Kim Callebaut[SUP] 2 [/SUP], Hendrik Jan Thibaut[SUP] 3 [/SUP], Karen Vanhoorelbeke[SUP] 1 4 [/SUP], Simon F De Meyer[SUP] 1 [/SUP], Wim Maes[SUP] 4 [/SUP], Nick Geukens[SUP] 4 [/SUP]
Affiliations
Abstract
To mitigate the massive COVID-19 burden caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), several vaccination campaigns were initiated. We performed a single-center observational trial to monitor the mid- (3 months) and long-term (10 months) adaptive immune response and to document breakthrough infections (BTI) in healthcare workers (n = 84) upon BNT162b2 vaccination in a real-world setting. Firstly, serology was determined through immunoassays. Secondly, antibody functionality was analyzed via in vitro binding inhibition and pseudovirus neutralization and circulating receptor-binding domain (RBD)-specific B cells were assessed. Moreover, the induction of SARS-CoV-2-specific T cells was investigated by an interferon-γ release assay combined with flowcytometric profiling of activated CD4[SUP]+[/SUP] and CD8[SUP]+[/SUP] T cells. Within individuals that did not experience BTI (n = 62), vaccine-induced humoral and cellular immune responses were not correlated. Interestingly, waning over time was more pronounced within humoral compared to cellular immunity. In particular, 45 of these 62 subjects no longer displayed functional neutralization against the delta variant of concern (VoC) at long-term follow-up. Noteworthily, we reported a high incidence of symptomatic BTI cases (17.11%) caused by alpha and delta VoCs, although vaccine-induced immunity was only slightly reduced compared to subjects without BTI at mid-term follow-up.
Keywords: BNT162b2 vaccine; SARS-CoV-2; breakthrough infection; healthcare workers; long-term monitoring; variants of concern.
. 2022 Jun 9;14(6):1257.
doi: 10.3390/v14061257.
High Incidence of SARS-CoV-2 Variant of Concern Breakthrough Infections Despite Residual Humoral and Cellular Immunity Induced by BNT162b2 Vaccination in Healthcare Workers: A Long-Term Follow-Up Study in Belgium
Bas Calcoen[SUP] 1 [/SUP], Nico Callewaert[SUP] 2 [/SUP], Aline Vandenbulcke[SUP] 1 [/SUP], Winnie Kerstens[SUP] 3 [/SUP], Maya Imbrechts[SUP] 4 [/SUP], Thomas Vercruysse[SUP] 3 [/SUP], Kai Dallmeier[SUP] 5 [/SUP], Johan Van Weyenbergh[SUP] 6 [/SUP], Piet Maes[SUP] 6 [/SUP], Xavier Bossuyt[SUP] 7 8 [/SUP], Dorinja Zapf[SUP] 9 [/SUP], Kersten Dieckmann[SUP] 9 [/SUP], Kim Callebaut[SUP] 2 [/SUP], Hendrik Jan Thibaut[SUP] 3 [/SUP], Karen Vanhoorelbeke[SUP] 1 4 [/SUP], Simon F De Meyer[SUP] 1 [/SUP], Wim Maes[SUP] 4 [/SUP], Nick Geukens[SUP] 4 [/SUP]
Affiliations
- PMID: 35746728
- DOI: 10.3390/v14061257
Abstract
To mitigate the massive COVID-19 burden caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), several vaccination campaigns were initiated. We performed a single-center observational trial to monitor the mid- (3 months) and long-term (10 months) adaptive immune response and to document breakthrough infections (BTI) in healthcare workers (n = 84) upon BNT162b2 vaccination in a real-world setting. Firstly, serology was determined through immunoassays. Secondly, antibody functionality was analyzed via in vitro binding inhibition and pseudovirus neutralization and circulating receptor-binding domain (RBD)-specific B cells were assessed. Moreover, the induction of SARS-CoV-2-specific T cells was investigated by an interferon-γ release assay combined with flowcytometric profiling of activated CD4[SUP]+[/SUP] and CD8[SUP]+[/SUP] T cells. Within individuals that did not experience BTI (n = 62), vaccine-induced humoral and cellular immune responses were not correlated. Interestingly, waning over time was more pronounced within humoral compared to cellular immunity. In particular, 45 of these 62 subjects no longer displayed functional neutralization against the delta variant of concern (VoC) at long-term follow-up. Noteworthily, we reported a high incidence of symptomatic BTI cases (17.11%) caused by alpha and delta VoCs, although vaccine-induced immunity was only slightly reduced compared to subjects without BTI at mid-term follow-up.
Keywords: BNT162b2 vaccine; SARS-CoV-2; breakthrough infection; healthcare workers; long-term monitoring; variants of concern.