Volume 28, Number 4—April 2022
Research
SARS-CoV-2 IgG Seroprevalence among Blood Donors as a Monitor of the COVID-19 Epidemic, Brazil
Table
Characteristics and severe acute respiratory syndrome coronavirus 2 IgG seroprevalence among blood donors, Brazil, March–December 2020
Characteristics | Total samples | Positive samples | Unadjusted seroprevalence, % (95% CI) | Test-adjusted seroprevalence, % (95% CI)* | Odds ratio (95% CI) |
---|---|---|---|---|---|
Total |
7,837 |
441 |
5.6 (5.1–6.2) |
5.2 (4.7–5.8) |
|
Sex | |||||
M | 4,284 | 273 | 6.4 (5.7–7.1) | 6.0 (5.3–6.9) | 1.4 (1.1–1.6) |
F |
3,553 |
168 |
4.7 (4.1–5.5) |
4.2 (3.5–5.0) |
|
Age range, y | |||||
16–30 | 2,895 | 153 | 5.3 (4.5–6.2) | 4.8 (4.0–5.8) | |
31–40 | 2,330 | 135 | 5.8 (4.9–6.8) | 5.4 (4.4–6.5) | |
41–50 | 1,701 | 115 | 6.8 (5.7–8.1) | 6.5 (5.3–7.9) | |
51–60 | 829 | 32 | 3.9 (2.8–5.4) | 3.2 (2.0–4.9) | |
61–70 |
82 |
6 |
7.3 (3.4–15.1) |
7.1 (2.7–15.8) |
|
Donor type | |||||
First-time donor | 1,483 | 72 | 4.9 (3.9–6.1) | 4.3 (3.2–5.7) | 0.8 (0.7–1.1) |
Repeat donor | 6,353 | 369 | 5.8 (5.3–6.4) | 5.4 (4.8–6.1) |
*Considering sensitivity of 90% and specificity of 99%. Analysis performed by Epitool by using Wilson’s confidence interval for apparent rate of positivity and Blaker’s CI for true rate of positivity.
1These authors contributed equally to this article.