Table 2.
Seroprevalence of IgG antibodies against SARS-CoV-2 and active infection in districts of Karnataka state (N = 15,624).
| Unit | Samplesa | % IgG against SARS-CoV2b | % active infectionb | % prevalence of COVID-19b | CIR | IFR |
|---|---|---|---|---|---|---|
| Karnataka | 15,624 | 16.8 (15.5–18.1) | 12.6 (11.5–13.8) | 27.7 (26.1–29.3) | 1 : 40 | 0.05% |
| Ballari | 406 | 22.7 (14.9–30.4) | 34.3 (25.2–43.3) | 43.5 (34–53) | 1 : 49 | 0.04% |
| Davanagere | 412 | 16.8 (9.8–23.7) | 29.1 (20.2–38) | 40.9 (31.3–50.5) | 1 : 62 | 0.06% |
| Udupi | 439 | 17 (10.3–23.7) | 22.6 (15–30.2) | 37 (28.2–45.9) | 1 : 34 | 0.05% |
| Vijayapura | 381 | 24.1 (15.9–32.4) | 13.8 (6.6–21.1) | 35.6 (25.9–45.3) | 1 : 112 | 0.02% |
| Raichur | 404 | 23.1 (15.2–30.9) | 12.1 (5.4–18.7) | 34.3 (25–43.6) | 1 : 76 | 0.02% |
| Chikmagalur | 436 | 12.3 (6.3–18.4) | 20.9 (13.1–28.7) | 32.1 (23.1–41.1) | 1 : 54 | 0.06% |
| Yadgir | 422 | 15.7 (9–22.5) | 18.5 (11.2–25.9) | 31.9 (23–40.8) | 1 : 62 | 0.02% |
| Hassan | 410 | 13.6 (7.1–20.1) | 21.1 (12.8–29.4) | 31 (21.7–40.3) | 1 : 44 | 0.08% |
| Belgaum | 430 | 23.9 (16.2–31.7) | 6.4 (1.4–11.4) | 30.3 (21.6–39) | 1 : 95 | 0.02% |
| Kalaburagi | 425 | 17.4 (10.5–24.4) | 14.4 (7.8–21) | 30.1 (21.4–38.7) | 1 : 60 | 0.04% |
| Bengaluru Urban Conglomerate | 3617 | 22.4 (19.6–25.3) | 9.2 (7.1–11.2) | 30.1 (26.9–33.3) | 1 : 23 | 0.07% |
| Ramanagar | 408 | 14.2 (7.5–20.8) | 16.1 (8.7–23.6) | 29.6 (20.4–38.7) | 1 : 76 | 0.02% |
| Tumakuru | 429 | 7 (1.9–12) | 25.1 (16.2–34.1) | 29.5 (20–39) | 1 : 82 | 0.08% |
| Bengaluru Rural | 432 | 15.6 (9–22.2) | 16.4 (9–23.8) | 29 (20.2–37.9) | 1 : 46 | 0.02% |
| Haveri | 417 | 15 (8.3–21.7) | 14.5 (7.8–21.3) | 28.8 (20.1–37.6) | 1 : 72 | 0.04% |
| Mysuru | 402 | 19.2 (11.9–26.6) | 8.4 (2.7–14) | 27.6 (18.9–36.3) | 1 : 34 | 0.07% |
| Dakshina Kannada | 430 | 15 (8.5–21.6) | 13.5 (6.9–20) | 27.4 (19–35.9) | 1 : 34 | 0.11% |
| Chitradurga | 411 | 10.3 (4.4–16.3) | 16 (8.5–23.4) | 26 (17.2–34.9) | 1 : 85 | 0.01% |
| Mandya | 414 | 18.8 (11.4–26.1) | 6.7 (1.3–12.1) | 25.5 (16.8–34.2) | 1 : 54 | 0.02% |
| Koppal | 427 | 20 (12.7–27.2) | 2.6 (0–6.2) | 22.6 (14.7–30.5) | 1 : 38 | 0.04% |
| Shivamogga | 426 | 8.1 (2.9–13.4) | 13.7 (6.8–20.5) | 21.8 (13.5–30) | 1 : 31 | 0.09% |
| Chamarajanagar | 383 | 16 (8.8–23.1) | 6.6 (1.1–12.1) | 21.3 (12.9–29.7) | 1 : 72 | 0.02% |
| Kodagu | 412 | 12.3 (6–18.5) | 8.7 (2.8–14.5) | 20.7 (12.6–28.9) | 1 : 56 | 0.03% |
| Bidar | 407 | 18.2 (10.9–25.4) | 0.7 (0–3.3) | 18.9 (11.2–26.5) | 1 : 64 | 0.04% |
| Uttara Kannada | 419 | 8.4 (3–13.8) | 8.7 (3–14.4) | 16.6 (9.1–24.1) | 1 : 33 | 0.04% |
| Kolar | 431 | 10.3 (4.5–16.1) | 6.7 (1.6–11.9) | 16.3 (9–23.6) | 1 : 59 | 0.04% |
| Chikkaballapur | 412 | 6.7 (1.6–11.8) | 5.8 (0–11.8) | 12.4 (4.8–20) | 1 : 28 | 0.07% |
| Bagalkot | 401 | 4.4 (0–8.9) | 9.7 (3.6–15.8) | 12.3 (5.3–19.4) | 1 : 31 | 0.08% |
| Gadag | 341 | 6.8 (1.3–12.3) | 2.7 (0–8.5) | 9.5 (1.6–17.4) | 1 : 14 | 0.11% |
| Dharwad | 440 | 7.6 (2.5–12.6) | 2 (0–5.5) | 9.2 (3.2–15.2) | 1 : 13 | 0.21% |
a
Included only samples that were mapped to individuals; CIR: case-to-infection ratio; IFR: infection fatality rate.
b
Adjusted for sensitivities and specificities of RAT, RT-PCR, and antibody testing kits and procedure.