Table 3 Relation between history of COVID-19 infection and NAbs titer
| Â | History of recent COVID-19 infection | ||
|---|---|---|---|
Yes | No | p value | |
| Â | Median (IQR) | Median(IQR) | |
AstraZeneca | |||
 NAbs Before vaccination | 91.91 (41.67–194.44) | 46.88 (14.07–264.71) |  < 0.001* |
 NAbs after 1st dose | 194.44 (75.37–441.18) | 115.81 (41.67–529.41) | 0.026* |
 NAbs after 2nd dose by 6 months | 294.12 (117.65–382.35) | 294.12 (88.24–500) | 0.579 |
Sinovac | |||
 NAbs Before vaccination | 99.26 (29.17–222.22) | 33.82 (14.62–67.71) | 0.033* |
 NAbs after 1st dose | 110.29 (56.99–294.12) | 110.29 (22.4–294.12) | 0.624 |
 NAbs after 2nd dose by 6 months | 382.35 (166.67–481.48) | 295 (80.88–529.41) | 0.278 |
Moderna and Pfizer | |||
 NAbs Before vaccination | 166.67 (46.88–500) | 58.85 (24.78–82.72) | 0.009* |
 NAbs after 1st dose | 294.12(82.72–3675) | 294.12 (73.53–500) | 0.823 |
 NAbs after 2nd dose by 6 months | 735 (294.12–5145) | 1470 (277.78–5880) | 0.670 |