Table 2.
Serum neutralizing antibody titers against SARS-CoV-2 variants across study groups.
| SARS-CoV-2 variant | Parameter | Study groupsa | |||
|---|---|---|---|---|---|
| Group 1 | Group 2 | Group 3 | |||
| SARS-CoV-2 Naïve | SARS-CoV-2 experienced | ||||
| Beta | GMT (SD) | 73.2 (612) | 6,172 (5,078) | 124 (316) | 122 (999) |
| Mean fold change reduction of NtAb titer (CI 95%)b | 19.4 (147.8) | 17.4 (27.5) | 13.1 (6.9) | 6.7 (84.9) | |
| Gamma | GMT (SD) | 241.7 (2,013) | 14,641 (6,777) | 256 (435) | 225 (1607) |
| Mean fold change reduction of NtAb titer (CI 95%)b | 5.88 (10.4) | 7.35 (16.0) | 6.3 (6.6) | 3.6 (4.8) | |
| Delta | GMT (SD) | 216.6 (3,274) | 77,157 (79,273) | 543 (1,138) | 231 (1,162) |
| Mean fold change reduction of NtAb titer (CI 95%)b | 6.57 (14.7) | 1.39 (1.62) | 3.0 (0.6) | 3.5 (4.1) | |
| Epsilon | GMT (SD) | 330 (4,309) | 8,047 (7,189) | 261 (324) | 283 (1,869) |
| Mean fold change reduction of NtAb titer (CI 95%)b | 4.3 (8.1) | 13.4 (15.4) | 6.2 (6.6) | 2.9 (2.2) | |
| (Wuhan-Hu-1) | GMT (SD) | 1,423 (5,173) | 107,541 (20,934) | 1,622 (2,259) | 442 (2,083) |
CI confidence interval, GMT geometric mean titer, NtAb neutralizing antibodies, SD standard deviation.
aGroup 1, nursing home residents fully vaccinated with the Comirnaty vaccine; Group 2, healthy individuals fully vaccinated with the Comirnaty vaccine; Group 3, unvaccinated, COVID-19 recovered individuals that required hospitalization in internal medicine or intensive care units.
bRelative to the NtAb titer against WA1/2020.