Figure 3.

Neutralization of the Delta and Omicron variants before and 3 months after booster BNT162b mRNA vaccine dose in NH residents.

Individual values, geometric mean neutralization titers (GMNT) and 95% confidence intervals are shown. Percentages and pie charts show the proportion of participants within each group that had detectable neutralization against the indicated variant. Serum neutralization titers of live B.1.617.2 (Delta, left) and B.1.1.529 (Omicron, right) SARS-CoV-2 strains determined for NH residents without (naive, blue) or with (recovered, red) COVID-19 before initial vaccination. Wilcoxon signed rank test was used for within-subjects comparisons. Mann-Whitney U test was performed to compare naive and recovered residents at 3 months. *p-values < 0·05; ****p-values < 0·0001; ns, not significant.