Table. SARS-CoV-2 Immunoreactivity of Plasma Samples From 100 Healthy Vaccinated Individualsa.
Serologic assay result | No. of participants (%) | P value (total positive vs negative)c | ||||
---|---|---|---|---|---|---|
BNT162b2 (n = 24) | ChAdOX1-S (n = 24) | Gam-COVID-Vac (n = 24) | BBIBP-CorV (n = 24) | BBIBP-CorV + BNT162b2 (n = 4)b | ||
ELISA | ||||||
Spike | ||||||
Negative | 0 | 5 (20.83) | 12 (50.00) | 17 (70.83) | 0 | .0002 (BNT162b2 vs Gam-COVID-Vac), .0001 (BNT162b2 vs BBIBP-CorV), .03 (ChAdOX1-S vs Gam-COVID-Vac), and .0005 (ChAdOX1-S vs BBIBP-CorV) |
Total positive | 24 (100.00) | 19 (79.17) | 12 (50.00) | 7 (29.17) | 4 (100.00) | |
Weak positive | 2 (8.33) | 2 (8.33) | 5 (20.83) | 4 (16.67) | 1 (25.00) | |
Positive | 22 (91.67) | 17 (70.83) | 7 (29.17) | 3 (12.50) | 3 (75.00) | |
NCP | ||||||
Negative | 23 (95.83) | 21 (87.50) | 23 (95.83) | 21 (87.50) | 3 (75.00) | NA |
Total positive | 1 (4.17) | 3 (12.50) | 1 (4.17) | 3 (12.50) | 1 (25.00) | |
Weak positive | 1 (4.17) | 2 (8.33) | 0 | 0 | 0 | |
Positive | 0 | 1 (4.17) | 1 (4.17) | 3 (12.50) | 1 (25.00) | |
Neutralizing antibody | ||||||
Washington strain | ||||||
Not detected | 5 (20.83) | 12 (50.00) | 18 (75.00) | 19 (79.17) | 1 (25.00) | .03 (BNT162b2 vs ChAdOX1-S), .0002 (BNT162b2 vs Gam-COVID-Vac), .00005 (BNT162b2 vs BBIBP-CorV), and .03 (ChAdOX1-S vs BBIBP-CorV) |
Detected | 19 (79.17) | 12 (50.00) | 6 (25.00) | 5 (20.83) | 3 (75.00) | |
≤1:40 | 14 (58.30) | 4 (16.70) | 4 (16.70) | 2 (8.33) | 2 (50.00) | |
>1:40 | 5 (20.83) | 8 (33.30) | 2 (8.33) | 3 (12.50) | 1 (25.00) | |
Delta variant | ||||||
Not detected | 17 (70.83) | 15 (62.50) | 22 (91.60) | 21 (87.50) | 3 (75.00) | .016 (ChAdOX1-S vs Gam-COVID-Vac) and .045 (ChAdOX1-S vs BBIBP-CorV) |
Detected | 7 (29.17) | 9 (37.50) | 2 (8.33) | 3 (12.50) | 1 (25.00) | |
≤1:40 | 4 (16.67) | 3 (12.50) | 1 (4.20) | 2 (8.33) | 0 | |
>1:40 | 3 (12.50) | 6 (25.00) | 1 (4.20) | 1 (4.20) | 1 (25.00) |
Determined by the spike-immunoglobulin G enzyme-linked immunoassay (ELISA), nucleocapsid protein (NCP)-ELISA, and end point absolute viral neutralization assay against the SARS-CoV-2 Washington strain and the B.1.617.2 (Delta) variant. Participants had received 1 of 4 COVID-19 vaccines: ChAdOX1-S (Covishield; Oxford/AstraZeneca), Gam-COVID-Vac (Sputnik V; Russian Direct Investment Fund), BBIBP-CorV (Sinopharm), or BNT162b2 (Pfizer/BioNTech).
The BBIBP-CorV + BNT162b2 group was not included in the statistical analysis because of the small sample size.
P values were recorded for the NCP-ELISA. The χ2 test was used to determine significance (<.05). NA, not applicable.