Table 1.
Populational characteristics, SARS-CoV-2 infection and seroreactivity.
| Case (n = 9) |
Control (n = 45) |
p Value | ||
|---|---|---|---|---|
| Characteristics | ||||
| Female, n (%) | 5 (55.6) | 25 (55.6) | >0.9999 * | |
| Age, mean | 40.2 | 40.6 | 0.9399 ‡ | |
| Age, median (IQR) | 38 (28.5–54) |
36 (30–54) |
||
| Age, range | 24–67 | 22–69 | ||
| Income | 0–3 minimum salaries | 3 (33.3) | 7 (15.6) | 0.4403 * |
| 4–6 minimum salaries | 2 (22.2) | 15 (33.3) | ||
| >6 minimum salaries | 4 (44.4) | 23 (51.1) | ||
| Comorbidities, yes, n (%) | 6 (66.7) | 28 (62.2) | 0.801 * | |
| Diabetes | 1 (11.1) | 5 (11.1) | ||
| Hypertension | 3 (33.3) | 15 (33.3) | ||
| Obesity | 3 (33.3) | 9 (20) | ||
| Asthma | 1 (11.1) | 4 (8.9) | ||
| Cardiopathy or nephropathy | 1 (11.1) | 1 (2.2) | ||
| Interval from first to second dose of vaccination, days median (IQR) | 28.0 (24.0–30.5) |
25.0 (23.0–35.0) |
0.0565 ‡ | |
| COVID-19-related information | ||||
| COVID-19 prior to vaccination, yes, n (%) | 2 (22.2) | 10 (22.2) | >0.9999 * | |
| Days of onset symptoms after full vaccination $, median (IQR) | 61 (49.3–78) | |||
| Days with symptoms on day of antigen testing after fully vaccinated, median (IQR) | 4 (2–6) | |||
| Antigen test after fully vaccinated $ | 7/9 positive | |||
| Days with symptoms on day of RT-qPCR testing after fully vaccinated, median (IQR) | 4 (2–6) | |||
| RT-qPCR testing after fully vaccinated $ | 9/9 positive | |||
| Hospitalization, yes, n (%) | 2 (22.2) | |||
| Oxygen requirement, yes, n (%) | 1 (11.1) | |||
| Symptoms on the day of testing, yes, n (%) | 8 (88.9) | |||
| Symptoms, n (%) | Fever | 6 (75.0) | ||
| Dry cough | 6 (75.0) | |||
| Sore throat | 3 (37.5) | |||
| Nasal discharge | 7 (87.5) | |||
| Chill | 3 (37.5) | |||
| Headache | 7 (87.5) | |||
| Myalgia | 5 (62.5) | |||
| Arthralgia | 1 (12.5) | |||
| Fatigue | 3 (37.5) | |||
| Chest pain | 2 (25.0) | |||
| Backache | 5 (62.5) | |||
| Shortness of breath | 1 (12.5) | |||
| Anosmia | 3 (37.5) | |||
| Dysgeusia (loss of taste) | 3 (37.5) | |||
| Conjunctivitis | 2 (25.0) | |||
| Loss of appetite | 1 (12.5) | |||
| Serological testing | ||||
| Before vaccination | Anti-nucleocapsid IgG positive, n (%) | 2 (22.2) | 10 (22.2) | >0.9999 ‡ |
| Anti-nucleocapsid IgG (RI), median (IQR) | 1.25 (0.75–1.6) |
1.02 (0.65–1.35) |
0.4391 ‡ | |
| Anti-spike-RBD IgG positive, n (%) | 2 (22.2) | 11 (24.4) | 0.8868 ‡ | |
| Anti-spike-RBD IgG (BAU/mL), median (IQR) | 11.78 (9.4–43.35) |
10.86 (9.5–32.5) |
0.4363 ‡ | |
| RBD-ACE2 inhibition (%), median (95% CI) | −9.99 (−16.3–18.9) |
1.19 (−1.1–7.0) |
0.0627 ‡ | |
| Peak response after fully vaccinated $ | Anti-nucleocapsid IgG positive, n (%) | 6 (66.7) | 35 (77.8) | 0.4766 ‡ |
| Anti-nucleocapsid IgG (RI), median (IQR) | 5.88 (1.6–8.9) |
4.48 (1.7–8.5) |
0.9143 ‡ | |
| Anti-spike-RBD IgG positive, n (%) | 9 (100.0) | 41 (91.1) | 0.3526 ‡ | |
| Anti-spike-RBD IgG (BAU/mL), median (IQR) | 228.8 (197.3–422.4) |
189.9 (82.5–496.0) |
0.8714 ‡ | |
| RBD-ACE2 inhibition (%), median (95% CI) | 63.8 (41.8–95.7) |
46.9 (30.8–61.5) |
0.1515 ‡ | |
$ 15 days after second dose of vaccine was considered fully vaccinated. RI: Reactivity Index. BAU: binding antibody units. IQR: interquartile. IgG: immunoglobulin G. RBD: receptor binding domain. ACE2: angiotensin-converting enzyme-2. ‡ Unpaired t-test. * Chi-square test.