Table 2.
Seroprevalence of SARS-CoV-2 by self-reported clinical characteristics
|
Point-of-care test |
Immunoassay |
||||
|---|---|---|---|---|---|
| Number of participants | Seroprevalence (95% CI) | Number of participants | Seroprevalence (95% CI) | ||
| Symptoms compatible with COVID-19* | |||||
| Asymptomatic | 40 325 | 2·5% (2·3–2·8) | 34 016 | 2·0% (1·8–2·3) | |
| Paucisymptomatic | 12 399 | 4·5% (4·0–5·0) | 10 669 | 3·9% (3·4–4·4) | |
| Symptomatic | 8351 | 16·9% (15·5–18·4) | 7273 | 16·9% (15·4–18·5) | |
| ≤14 days before study visit | 2397 | 13·9% (11·8–16·4) | 2155 | 14·0% (11·8–16·5) | |
| >14 days before study visit | 5954 | 18·0% (16·4–19·8) | 5118 | 18·0% (16·3–19·9) | |
| PCR status | |||||
| Never done | 59 568 | 4·6% (4·3–4·9) | 50 594 | 4·2% (3·8–4·5) | |
| Negative | 1249 | 7·9% (6·0–10·3) | 1134 | 8·0% (6·0–10·6) | |
| Positive (≤14 days before study visit) | 35 | 45·6% (25·0–67·8) | 31 | 65·8% (41·5–83·9) | |
| Positive (>14 days before study visit) | 213 | 88·6% (82·3–92·8) | 195 | 90·1% (84·3–93·9) | |
| Contact with confirmed case | |||||
| No contact | 55 989 | 3·9% (3·6–4·2) | 47 385 | 3·4% (3·1–3·7) | |
| Household member | 1011 | 31·4% (26·5–36·8) | 860 | 37·4% (31·8–43·3) | |
| Non-cohabitating family member or friend | 1467 | 13·2% (11·0–15·8) | 1284 | 13·7% (11·2–16·7) | |
| Co-worker | 1579 | 10·6% (8·5–13·1) | 1461 | 9·9% (8·0–12·2) | |
| Cleaning staff, housemaid, or caregiver | 83 | 13·5% (6·3–26·5) | 78 | 12·4% (7·0–21·0) | |
| Client† | 940 | 11·7% (9·1–14·9) | 888 | 11·2% (8·6–14·4) | |
| Contact with symptomatic person | |||||
| No contact | 50 691 | 3·2% (3·0–3·5) | 42 894 | 2·7% (2·4–3·0) | |
| Household member | 4503 | 15·1% (13·3–17·0) | 3728 | 15·6% (13·6–17·9) | |
| Non-cohabitating family member or friend | 2351 | 12·7% (10·7–14·9) | 2037 | 12·2% (10·0–14·7) | |
| Co-worker | 2382 | 10·7% (9·0–12·6) | 2221 | 10·1% (8·4–12·1) | |
| Cleaning staff, housemaid, or caregiver | 109 | 8·8% (3·9–18·8) | 96 | 6·1% (2·9–12·3) | |
| Client† | 1033 | 10·0% (7·8–12·8) | 980 | 10·2% (7·8–13·1) | |
SARS-CoV-2=severe acute respiratory syndrome coronavirus 2.
*
Asymptomatic (no symptoms), paucisymptomatic (1–2 symptoms without anosmia or ageusia), and symptomatic (anosmia or ageusia, or at least three symptoms among fever; chills; severe tiredness; sore throat; cough; shortness of breath; headache; or nausea, vomiting, or diarrhoea).
†
Client or patient if health-care worker.