Rune M. Pedersen, Line L. Bang, Ditte S. Tornby, Lone W. Madsen, Dorte K. Holm, Thomas V. Sydenham, Isik S. Johansen, Thøger G. Jensen, Ulrik S. Justesen, and Thomas E. Andersen
Figure. Neutralization of SARS-CoV-2 variants among vaccine-boosted persons with and without prior Omicron BA.1/BA.2 infections, Denmark. A) PRNT90 titers against SARS-CoV-2 Delta variant and Omicron variants BA.1, BA.2, and BA.5. B) Correlation between the levels of spike antibodies and PRNT90 titers. Participants received 3 doses of BNT162b2 (Pfizer-BioNTech, https://www.pfizer.com), 2 initial vaccines and a booster dose. We analyzed titers for 24 vaccinated participants (blue dots) who received 3 BNT162b2 doses only and 12 convalescent participants (red dots) who received 3 vaccine doses and had Omicron BA.1/BA.2 infection. For statistical analysis, a Kruskal-Wallis test was applied initially to account for the multiple comparisons problem. Subsequently, unpaired PRNT90 titers were compared with the Wilcoxon rank-sum test, whereas paired PRNT90 titers were compared with the Wilcoxon sign rank test. Red horizontal lines indicate neutralization threshold; horizontal bars indicate median neutralization titer for each SARS-CoV-2 strain. BAU, binding antibody units; C, convalescent participant; PRNT90, plaque reduction neutralization tests with plaque reduction >90%; V, vaccinated participant.