Sera from individuals who had been infected with SARS-CoV-2 (a-c; n = 10, ~1-month post-infection) or vaccinated with the Pfizer-BioNTech mRNA vaccine (d-f; n = 10) were tested for neutralization of the indicated SARS-CoV-2 strains (WA1/2020 D614G (a, b, c, e, f, g), B.1.1.7 (a, e), Wash SA-B.1.351 (b, f), or Wash BR-B.1.1.248 (c, g) using a FRNT in Vero-TMPRSS2 cells. Results are from one experiment performed in duplicate, with some exceptions due to limited sample. GMT values are shown above each graph. Dotted line represents the limit of detection of the assay. Two-tailed Wilcoxon matched-pairs signed rank test: Convalescent sera: D614G vs. B.1.1.7, P = 0.0039; D614G vs. Wash SA-B.1.351, P = 0.0020; D614G vs. Wash BR-B.1.1.248, P = 0.0020. Vaccine sera: D614G vs. B.1.1.7, P = 0.0039; D614G vs. Wash SA-B.1.351, P = 0.0020; D614G vs. Wash BR-B.1.1.248, P = 0.0020. d, h, Heat maps of the relative neutralizing activity of sera from convalescent (d) or vaccinated (h) individuals against indicated SARS-CoV-2 viruses compared to WA1/2020. Blue, reduction; red, increase.