Neutralization heterogeneity of United Kingdom and South-African SARS CoV-2 variants in BNT162b2-vaccinated or convalescent COVID-19 healthcare workers

Marot, S. S.; Malet, I.; Jary, A.; Leducq, V.; Abdi, B.; Teyssou, E.; Soulie, C.; Wirden, M.; Rodriguez, C.; Fourati, S.; Pawlotsky, J.-M.; Boutolleau, D.; Burrel, S.; Calvez, V.; Marcelin, A.-G.

doi:10.1101/2021.03.05.434089

bioRxiv · 10.1101/2021.03.05.434089

Neutralization heterogeneity of United Kingdom and South-African SARS CoV-2 variants in BNT162b2-vaccinated or convalescent COVID-19 healthcare workers

Marot, S. S.·Malet, I.·Jary, A.·Leducq, V.·Abdi, B.·Teyssou, E.·Soulie, C.·Wirden, M.·Rodriguez, C.·Fourati, S.·Pawlotsky, J.-M.·Boutolleau, D.·Burrel, S.·Calvez, V.·Marcelin, A.-G.

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Abstract

There are concerns about neutralizing antibodies (NAb) potency against the newly emerged VOC202012/01 (UK) and 501Y.V2 (SA) SARS-CoV-2 variants in mRNA-vaccinated subjects and in recovered COVID-19 patients. We used a viral neutralization test with a strict 100% neutralizing criterion on UK and SA clinical isolates in comparison with a globally distributed D614G SARS-CoV-2 strain. In two doses BNT162b2-vaccinated healthcare workers (HCW), despite heterogeneity in neutralizing capacity against the three SARS-CoV-2 strains, most of the sera harbored at least a NAb titer [≥] 1:10 suggesting a certain humoral protection activity either on UK or SA variants. However, six months after mild forms of COVID-19, an important proportion of HCW displayed no neutralizing activity against SA strain. This result supports strong recommendations for vaccination of previously infected subjects.

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Marot, S. S., Malet, I., Jary, A., Leducq, V., Abdi, B., Teyssou, E., Soulie, C., Wirden, M., Rodriguez, C., Fourati, S., Pawlotsky, J.-M., Boutolleau, D., Burrel, S., Calvez, V., Marcelin, A.-G.. 2021-03-05. Neutralization heterogeneity of United Kingdom and South-African SARS CoV-2 variants in BNT162b2-vaccinated or convalescent COVID-19 healthcare workers. https://doi.org/10.1101/2021.03.05.434089

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